diff --git a/src/cocoatweet/api/status/update.cc b/src/cocoatweet/api/status/update.cc
index 5d689e1..bc36ae4 100644
--- a/src/cocoatweet/api/status/update.cc
+++ b/src/cocoatweet/api/status/update.cc
@@ -53,7 +53,7 @@ void Update::process(std::weak_ptr<CocoaTweet::OAuth::OAuth1> _oauth,
   {
     std::vector<std::string> tmp;
     for (const auto& [key, value] : oauthParam) {
-      tmp.push_back(key + "=" + value);
+      tmp.push_back(key + "=" + CocoaTweet::Util::urlEncode(value));
     }
     std::stringstream os;
     std::copy(tmp.begin(), tmp.end(), std::ostream_iterator<std::string>(os, ","));
diff --git a/src/cocoatweet/oauth/oauth.cc b/src/cocoatweet/oauth/oauth.cc
index 2331b0c..6ac8217 100644
--- a/src/cocoatweet/oauth/oauth.cc
+++ b/src/cocoatweet/oauth/oauth.cc
@@ -43,7 +43,7 @@ std::map<std::string, std::string> OAuth1::signature(
   std::cout << "hmac-sha1 : " << k64Sha1 << std::endl;
 
   auto ret = std::map<std::string, std::string>{
-      {"oauth_signature", CocoaTweet::Util::urlEncode(k64Sha1)}};
+      {"oauth_signature", k64Sha1}};
   return ret;
 }