diff --git a/influxdb/client.py b/influxdb/client.py
index 2b6dc689..a8adb915 100644
--- a/influxdb/client.py
+++ b/influxdb/client.py
@@ -113,7 +113,7 @@ def __init__(self,
             self._port)
 
         self._headers = {
-            'Content-type': 'application/json',
+            'Content-Type': 'application/json',
             'Accept': 'text/plain'
         }
 
@@ -283,7 +283,7 @@ def write(self, data, params=None, expected_response_code=204,
         :rtype: bool
         """
         headers = self._headers
-        headers['Content-type'] = 'application/octet-stream'
+        headers['Content-Type'] = 'application/octet-stream'
 
         if params:
             precision = params.get('precision')