diff --git a/python/sglang/environ.py b/python/sglang/environ.py
new file mode 100644
index 000000000..ce2e39032
--- /dev/null
+++ b/python/sglang/environ.py
@@ -0,0 +1,275 @@
+import os
+import subprocess
+import warnings
+from contextlib import ExitStack, contextmanager
+from typing import Any
+
+
+class EnvField:
+    def __init__(self, default: Any):
+        self.default = default
+        # NOTE: we use None to indicate whether the value is set or not
+        # If the value is manually set to None, we need mark it as _set_to_none.
+        # Always use clear() to reset the value, which leads to the default fallback.
+        self._set_to_none = False
+
+    def __set_name__(self, owner, name):
+        self.name = name
+
+    def parse(self, value: str) -> Any:
+        raise NotImplementedError()
+
+    def get(self) -> Any:
+        value = os.getenv(self.name)
+        if self._set_to_none:
+            assert value is None
+            return None
+
+        if value is None:
+            return self.default
+
+        try:
+            return self.parse(value)
+        except ValueError as e:
+            warnings.warn(
+                f'Invalid value for {self.name}: {e}, using default "{self.default}"'
+            )
+            return self.default
+
+    def is_set(self):
+        # NOTE: If None is manually set, it is considered as set.
+        return self.name in os.environ or self._set_to_none
+
+    def get_set_value_or(self, or_value: Any):
+        # NOTE: Ugly usage, but only way to get custom default value.
+        return self.get() if self.is_set() else or_value
+
+    def set(self, value: Any):
+        if value is None:
+            self._set_to_none = True
+            os.environ.pop(self.name, None)
+        else:
+            self._set_to_none = False
+            os.environ[self.name] = str(value)
+
+    @contextmanager
+    def override(self, value: Any):
+        backup_present = self.name in os.environ
+        backup_value = os.environ.get(self.name)
+        backup_set_to_none = self._set_to_none
+        self.set(value)
+        yield
+        if backup_present:
+            os.environ[self.name] = backup_value
+        else:
+            os.environ.pop(self.name, None)
+        self._set_to_none = backup_set_to_none
+
+    def clear(self):
+        os.environ.pop(self.name, None)
+        self._set_to_none = False
+
+    @property
+    def value(self):
+        return self.get()
+
+
+class EnvStr(EnvField):
+    def parse(self, value: str) -> str:
+        return value
+
+
+class EnvBool(EnvField):
+    def parse(self, value: str) -> bool:
+        value = value.lower()
+        if value in ["true", "1", "yes", "y"]:
+            return True
+        if value in ["false", "0", "no", "n"]:
+            return False
+        raise ValueError(f'"{value}" is not a valid boolean value')
+
+
+class EnvInt(EnvField):
+    def parse(self, value: str) -> int:
+        try:
+            return int(value)
+        except ValueError:
+            raise ValueError(f'"{value}" is not a valid integer value')
+
+
+class EnvFloat(EnvField):
+    def parse(self, value: str) -> float:
+        try:
+            return float(value)
+        except ValueError:
+            raise ValueError(f'"{value}" is not a valid float value')
+
+
+class Envs:
+    # fmt: off
+
+    # Model & File Download
+    SGLANG_USE_MODELSCOPE = EnvBool(False)
+
+    # Test & Debug
+    SGLANG_IS_IN_CI = EnvBool(False)
+    SGLANG_AMD_CI = EnvBool(False)
+    SGLANG_TEST_RETRACT = EnvBool(False)
+    SGLANG_SET_CPU_AFFINITY = EnvBool(False)
+    SGLANG_PROFILE_WITH_STACK = EnvBool(True)
+    SGLANG_RECORD_STEP_TIME = EnvBool(False)
+    SGLANG_GC_LOG = EnvBool(False)
+    SGLANG_FORCE_SHUTDOWN = EnvBool(False)
+    SGLANG_DEBUG_MEMORY_POOL = EnvBool(False)
+    SGLANG_TEST_REQUEST_TIME_STATS = EnvBool(False)
+    SGLANG_DISABLE_TP_MEMORY_INBALANCE_CHECK = EnvBool(False)
+    SGLANG_DISABLE_REQUEST_LOGGING = EnvBool(False)
+
+    # Model Parallel
+    SGLANG_USE_MESSAGE_QUEUE_BROADCASTER = EnvBool(True)
+
+    # Constrained Decoding
+    SGLANG_DISABLE_OUTLINES_DISK_CACHE = EnvBool(True)
+    SGLANG_GRAMMAR_TIMEOUT = EnvFloat(300)
+
+    # Hi-Cache
+    SGLANG_HICACHE_HF3FS_CONFIG_PATH = EnvStr(None)
+
+    # Mooncake KV Transfer
+    SGLANG_MOONCAKE_CUSTOM_MEM_POOL = EnvBool(False)
+    ENABLE_ASCEND_TRANSFER_WITH_MOONCAKE = EnvBool(False)
+
+    # AMD & ROCm
+    SGLANG_USE_AITER = EnvBool(False)
+    SGLANG_ROCM_FUSED_DECODE_MLA = EnvBool(False)
+
+    # Quantization
+    SGLANG_INT4_WEIGHT = EnvBool(False)
+    SGLANG_CPU_QUANTIZATION = EnvBool(False)
+    SGLANG_USE_DYNAMIC_MXFP4_LINEAR = EnvBool(False)
+    SGLANG_FORCE_FP8_MARLIN = EnvBool(False)
+
+    # Flashinfer
+    SGLANG_IS_FLASHINFER_AVAILABLE = EnvBool(True)
+    SGLANG_ENABLE_FLASHINFER_GEMM = EnvBool(False)
+
+    # Triton
+    SGLANG_TRITON_DECODE_ATTN_STATIC_KV_SPLITS = EnvBool(False)
+
+    # Torch Compile
+    SGLANG_ENABLE_TORCH_COMPILE = EnvBool(False)
+
+    # EPLB
+    SGLANG_EXPERT_LOCATION_UPDATER_LOG_INPUT = EnvBool(False)
+    SGLANG_EXPERT_LOCATION_UPDATER_CANARY = EnvBool(False)
+    SGLANG_EXPERT_LOCATION_UPDATER_LOG_METRICS = EnvBool(False)
+    SGLANG_LOG_EXPERT_LOCATION_METADATA = EnvBool(False)
+
+    # TBO
+    SGLANG_TBO_DEBUG = EnvBool(False)
+
+    # DeepGemm
+    SGLANG_ENABLE_JIT_DEEPGEMM = EnvBool(True)
+    SGLANG_JIT_DEEPGEMM_PRECOMPILE = EnvBool(True)
+    SGLANG_JIT_DEEPGEMM_COMPILE_WORKERS = EnvInt(4)
+    SGLANG_IN_DEEPGEMM_PRECOMPILE_STAGE = EnvBool(False)
+    SGLANG_DG_CACHE_DIR = EnvStr(os.path.expanduser("~/.cache/deep_gemm"))
+    SGLANG_DG_USE_NVRTC = EnvBool(False)
+    SGLANG_USE_DEEPGEMM_BMM = EnvBool(False)
+
+    # sgl-kernel
+    SGLANG_SKIP_SGL_KERNEL_VERSION_CHECK = EnvBool(False)
+
+    # vLLM dependencies
+    USE_VLLM_CUSTOM_ALLREDUCE = EnvBool(False)
+    USE_VLLM_CUTLASS_W8A8_FP8_KERNEL = EnvBool(False)
+
+    USE_TRITON_W8A8_FP8_KERNEL = EnvBool(False)
+    RETURN_ORIGINAL_LOGPROB = EnvBool(False)
+    SGLANG_ALLOW_OVERWRITE_LONGER_CONTEXT_LEN = EnvBool(False)
+    SGLANG_MOE_PADDING = EnvBool(False)
+    SGLANG_CUTLASS_MOE = EnvBool(False)
+    HF_HUB_DISABLE_XET = EnvBool(False)
+    DISABLE_OPENAPI_DOC = EnvBool(False)
+    SGLANG_ENABLE_TORCH_INFERENCE_MODE = EnvBool(False)
+    SGLANG_IS_FIRST_RANK_ON_NODE = EnvBool(True)
+    SGLANG_SUPPORT_CUTLASS_BLOCK_FP8 = EnvBool(False)
+    SGLANG_SYNC_TOKEN_IDS_ACROSS_TP = EnvBool(False)
+    SGLANG_ENABLE_COLOCATED_BATCH_GEN = EnvBool(False)
+
+    # fmt: on
+
+
+envs = Envs()
+
+
+def _convert_SGL_to_SGLANG():
+    for key, value in os.environ.items():
+        if key.startswith("SGL_"):
+            new_key = key.replace("SGL_", "SGLANG_", 1)
+            warnings.warn(
+                f"Environment variable {key} is deprecated, please use {new_key}"
+            )
+            os.environ[new_key] = value
+
+
+_convert_SGL_to_SGLANG()
+
+
+def example_with_exit_stack():
+    # Use this style of context manager in unit test
+    exit_stack = ExitStack()
+    exit_stack.enter_context(envs.SGLANG_TEST_RETRACT.override(False))
+    assert envs.SGLANG_TEST_RETRACT.value is False
+    exit_stack.close()
+    assert envs.SGLANG_TEST_RETRACT.value is None
+
+
+def example_with_subprocess():
+    command = ["python", "-c", "import os; print(os.getenv('SGLANG_TEST_RETRACT'))"]
+    with envs.SGLANG_TEST_RETRACT.override(True):
+        process = subprocess.Popen(
+            command, stdout=subprocess.PIPE, stderr=subprocess.PIPE
+        )
+        process.wait()
+        output = process.stdout.read().decode("utf-8").strip()
+        assert output == "True"
+
+    process = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    output = process.stdout.read().decode("utf-8").strip()
+    assert output == "None"
+
+
+def examples():
+    # Example usage for envs
+    envs.SGLANG_TEST_RETRACT.clear()
+    assert envs.SGLANG_TEST_RETRACT.value is False
+
+    envs.SGLANG_TEST_RETRACT.set(None)
+    assert envs.SGLANG_TEST_RETRACT.is_set() and envs.SGLANG_TEST_RETRACT.value is None
+
+    envs.SGLANG_TEST_RETRACT.clear()
+    assert not envs.SGLANG_TEST_RETRACT.is_set()
+
+    envs.SGLANG_TEST_RETRACT.set(True)
+    assert envs.SGLANG_TEST_RETRACT.value is True
+
+    with envs.SGLANG_TEST_RETRACT.override(None):
+        assert (
+            envs.SGLANG_TEST_RETRACT.is_set() and envs.SGLANG_TEST_RETRACT.value is None
+        )
+
+    assert envs.SGLANG_TEST_RETRACT.value is True
+
+    envs.SGLANG_TEST_RETRACT.set(None)
+    with envs.SGLANG_TEST_RETRACT.override(True):
+        assert envs.SGLANG_TEST_RETRACT.value is True
+
+    assert envs.SGLANG_TEST_RETRACT.is_set() and envs.SGLANG_TEST_RETRACT.value is None
+
+    example_with_exit_stack()
+    example_with_subprocess()
+
+
+if __name__ == "__main__":
+    examples()
diff --git a/python/sglang/srt/utils.py b/python/sglang/srt/utils.py
index 1e60208fc..0301a8dbc 100644
--- a/python/sglang/srt/utils.py
+++ b/python/sglang/srt/utils.py
@@ -191,6 +191,7 @@ _warned_bool_env_var_keys = set()
 
 
 def get_bool_env_var(name: str, default: str = "false") -> bool:
+    # FIXME: move your environment variable to sglang.environ
     value = os.getenv(name, default)
     value = value.lower()
 
@@ -208,6 +209,7 @@ def get_bool_env_var(name: str, default: str = "false") -> bool:
 
 
 def get_int_env_var(name: str, default: int = 0) -> int:
+    # FIXME: move your environment variable to sglang.environ
     value = os.getenv(name)
     if value is None or not value.strip():
         return default