diff --git a/docs/tutorials/INSTALL.md b/docs/tutorials/INSTALL.md
index 3833f9b754074d971eee4ba61939a3ac47312266..6dfdc7b09062726b3da8a48d6be75a889596acdd 100644
--- a/docs/tutorials/INSTALL.md
+++ b/docs/tutorials/INSTALL.md
@@ -101,6 +101,8 @@ pip install -r requirements.txt
 
     ```pip install git+https://github.com/philferriere/cocoapi.git#subdirectory=PythonAPI```
 
+2. If you are using Python <= 3.6, `pycocotools` installing may failed with error like `distutils.errors.DistutilsError: Could not find suitable distribution for Requirement.parse('cython>=0.27.3')`, please install `cython` firstly, for example `pip install cython`
+
 After installation, make sure the tests pass:
 
 ```shell
diff --git a/docs/tutorials/INSTALL_cn.md b/docs/tutorials/INSTALL_cn.md
index 88357d1595fc2b30b50f972c9c1b3a5cee7b6ee5..0fde61bf91870a4ebe9debcef6fbc8ed1cea7ce5 100644
--- a/docs/tutorials/INSTALL_cn.md
+++ b/docs/tutorials/INSTALL_cn.md
@@ -91,6 +91,8 @@ pip install -r requirements.txt
 
     ```pip install git+https://github.com/philferriere/cocoapi.git#subdirectory=PythonAPI```
 
+2. 若您使用的是Python <= 3.6的版本，安装`pycocotools`可能会报错`distutils.errors.DistutilsError: Could not find suitable distribution for Requirement.parse('cython>=0.27.3')`, 您可通过先安装`cython`如`pip install cython`解决该问题
+
 
 安装后确认测试通过：