diff --git a/src/WebAssert.php b/src/WebAssert.php
index b03c9829e..3f5745b36 100644
--- a/src/WebAssert.php
+++ b/src/WebAssert.php
@@ -494,17 +494,22 @@ public function elementTextNotContains($selectorType, $selector, $text)
     /**
      * Checks that specific element contains HTML.
      *
-     * @param string       $selectorType element selector type (css, xpath)
-     * @param string|array $selector     element selector
-     * @param string       $html         expected text
+     * Comparison is case-insensitive by default. You can enable case-sensitive
+     * mode via passing `true` in the fourth argument.
+     *
+     * @param string       $selectorType  element selector type (css, xpath)
+     * @param string|array $selector      element selector
+     * @param string       $html          expected text
+     * @param bool         $caseSensitive use case sensitive comparison
      *
      * @throws ElementHtmlException
      */
-    public function elementContains($selectorType, $selector, $html)
+    public function elementContains($selectorType, $selector, $html, $caseSensitive = false)
     {
         $element = $this->elementExists($selectorType, $selector);
         $actual = $element->getHtml();
-        $regex = '/'.preg_quote($html, '/').'/ui';
+        $regex = '/'.preg_quote($html, '/').'/u';
+        if ($caseSensitive === false) $regex .= 'i';
 
         $message = sprintf(
             'The string "%s" was not found in the HTML of the %s.',
@@ -518,17 +523,22 @@ public function elementContains($selectorType, $selector, $html)
     /**
      * Checks that specific element does not contains HTML.
      *
-     * @param string       $selectorType element selector type (css, xpath)
-     * @param string|array $selector     element selector
-     * @param string       $html         expected text
+     * Comparison is case-insensitive by default. You can enable case-sensitive
+     * mode via passing `true` in the fourth argument.
+     *
+     * @param string       $selectorType  element selector type (css, xpath)
+     * @param string|array $selector      element selector
+     * @param string       $html          expected text
+     * @param bool         $caseSensitive use case sensitive comparison
      *
      * @throws ElementHtmlException
      */
-    public function elementNotContains($selectorType, $selector, $html)
+    public function elementNotContains($selectorType, $selector, $html, $caseSensitive = false)
     {
         $element = $this->elementExists($selectorType, $selector);
         $actual = $element->getHtml();
-        $regex = '/'.preg_quote($html, '/').'/ui';
+        $regex = '/'.preg_quote($html, '/').'/u';
+        if ($caseSensitive === false) $regex .= 'i';
 
         $message = sprintf(
             'The string "%s" appears in the HTML of the %s, but it should not.',
diff --git a/tests/WebAssertTest.php b/tests/WebAssertTest.php
index 22c58b7bc..467c8f5d4 100644
--- a/tests/WebAssertTest.php
+++ b/tests/WebAssertTest.php
@@ -927,31 +927,38 @@ public function testElementContains()
         ;
 
         $this->session
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('getPage')
             ->will($this->returnValue($page))
         ;
 
         $page
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('find')
             ->with('css', 'h2 > span')
             ->will($this->returnValue($element))
         ;
 
         $element
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('getHtml')
             ->will($this->returnValue('element html'))
         ;
 
-        $this->assertCorrectAssertion('elementContains', array('css', 'h2 > span', 'html'));
+        $this->assertCorrectAssertion('elementContains', array('css', 'h2 > span', 'HTML'));
+        $this->assertCorrectAssertion('elementContains', array('css', 'h2 > span', 'html', true));
         $this->assertWrongAssertion(
             'elementContains',
             array('css', 'h2 > span', 'text'),
             'Behat\\Mink\\Exception\\ExpectationException',
             'The string "text" was not found in the HTML of the element matching css "h2 > span".'
         );
+        $this->assertWrongAssertion(
+            'elementContains',
+            array('css', 'h2 > span', 'Html', true),
+            'Behat\\Mink\\Exception\\ExpectationException',
+            'The string "Html" was not found in the HTML of the element matching css "h2 > span".'
+        );
     }
 
     public function testElementNotContains()
@@ -967,31 +974,38 @@ public function testElementNotContains()
         ;
 
         $this->session
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('getPage')
             ->will($this->returnValue($page))
         ;
 
         $page
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('find')
             ->with('css', 'h2 > span')
             ->will($this->returnValue($element))
         ;
 
         $element
-            ->expects($this->exactly(2))
+            ->expects($this->exactly(4))
             ->method('getHtml')
-            ->will($this->returnValue('element html'))
+            ->will($this->returnValue('element Html'))
         ;
 
-        $this->assertCorrectAssertion('elementNotContains', array('css', 'h2 > span', 'text'));
+        $this->assertCorrectAssertion('elementNotContains', array('css', 'h2 > span', 'Text'));
+        $this->assertCorrectAssertion('elementNotContains', array('css', 'h2 > span', 'html', true));
         $this->assertWrongAssertion(
             'elementNotContains',
             array('css', 'h2 > span', 'html'),
             'Behat\\Mink\\Exception\\ExpectationException',
             'The string "html" appears in the HTML of the element matching css "h2 > span", but it should not.'
         );
+        $this->assertWrongAssertion(
+            'elementNotContains',
+            array('css', 'h2 > span', 'Html', true),
+            'Behat\\Mink\\Exception\\ExpectationException',
+            'The string "Html" appears in the HTML of the element matching css "h2 > span", but it should not.'
+        );
     }
 
     public function testElementAttributeContains()