diff --git a/plugins/censor/censor.php b/plugins/censor/censor.php
index ede620d..659dd4e 100644
--- a/plugins/censor/censor.php
+++ b/plugins/censor/censor.php
@@ -116,7 +116,7 @@ class Censor extends Utils {
         if ($this->config->get("censor", "badword")) {
 
             foreach ($this->bad_word_list["normal"] as $value) {
-                if (stripos($message, $value[0]) !== false) {
+                if (mb_stripos($message, $value[0]) !== false) {
                     $badword_found = true;
                     $badword = $value[0];
                     $multi = $value[1];
@@ -176,7 +176,7 @@ class Censor extends Utils {
         if ($this->config->get("censor", "badname")) {
 
             foreach ($this->bad_name_list["normal"] as $value) {
-                if (stripos($name, $value[0]) !== false) {
+                if (mb_stripos($name, $value[0]) !== false) {
                     $badname_found = true;
                     $badname = $value[0];
                     $multi = $value[1];
@@ -242,8 +242,8 @@ class Censor extends Utils {
             $badword = trim($badword);
 
             /* Decide to move filter to regex filter or to normal filter */
-            if (stripos($badword, 'regexp:') === 0) {
-                $regexp[] = array(substr($badword, 7), $multi);
+            if (mb_stripos($badword, 'regexp:') === 0) {
+                $regexp[] = array(mb_substr($badword, 7), $multi);
             } else {
                 $normal[] = array($badword, $multi);
             }
@@ -260,8 +260,8 @@ class Censor extends Utils {
             $badname = trim($badname);
 
             /* Decide to move filter to regex filter or to normal filter */
-            if (stripos($badname, 'regexp:') === 0) {
-                $regexp[] = array(substr($badname, 7), $multi);
+            if (mb_stripos($badname, 'regexp:') === 0) {
+                $regexp[] = array(mb_substr($badname, 7), $multi);
             } else {
                 $normal[] = array($badname, $multi);
             }