diff --git a/pyexcel-io.yml b/pyexcel-io.yml
index 339c1c9..626155e 100644
--- a/pyexcel-io.yml
+++ b/pyexcel-io.yml
@@ -9,7 +9,6 @@ copyright_year: 2015-2022
 moban_command: false
 is_on_conda: true
 dependencies:
-  - chardet
   - lml>=0.0.4
 test_dependencies:
   - pyexcel
@@ -17,6 +16,7 @@ test_dependencies:
   - SQLAlchemy
   - pyexcel-xlsxw
 extra_dependencies:
+  - chardet
   - xls:
     - pyexcel-xls>=0.6.0
   - xlsx:
diff --git a/pyexcel_io/readers/csvz.py b/pyexcel_io/readers/csvz.py
index cae0383..36af596 100644
--- a/pyexcel_io/readers/csvz.py
+++ b/pyexcel_io/readers/csvz.py
@@ -10,7 +10,11 @@
 import zipfile
 from io import BytesIO
 
-import chardet
+try:
+    import chardet
+except ImportError:
+    print("Please install chardet so as to use csvz")
+    raise
 from pyexcel_io import constants
 from pyexcel_io.sheet import NamedContent
 from pyexcel_io._compact import StringIO