How to remove a comment based on it's field value?
This code should work for you

function THEME_preprocess_node(&amp;$variables) {
  global $language;
  foreach ($variables['content']['comments']['comments'] as $key =&gt; $comment) {
    if ($comment['field_language']['#items'][0]['value'] != $language-&gt;language) {
      unset($variables['content']['comments']['comments'][$key]);
    }
  }     
}