How to create field template for displaying taxonomy terms as list in full content page?
Use template_preprocess_field()
You can try something like this in your template.php:
/**
 * Implements template_preprocess_field().
 */
function YOURTHEMENAME_preprocess_field(&amp;$variables, $hook) {
  if ($variables['element']['#object']-&gt;type == 'YOUR_CONTENT_TYPE_NAME') {
    $output = '';

    // Render the label, if it's not hidden.
    if (!$variables['label_hidden']) {
      $output .= '&lt;h3 class=&quot;field-label&quot;&gt;' . $variables['label'] . ': &lt;/h3&gt;';
    }

    // Render the items.
    $output .= ($variables['element']['#label_display'] == 'inline') ? '&lt;ul class=&quot;links inline&quot;&gt;' : '&lt;ul class=&quot;list&quot;&gt;';
    foreach ($variables['items'] as $delta =&gt; $item) {
      $output .= '&lt;li class=&quot;taxonomy-term-reference-' . $delta . '&quot;' . $variables['item_attributes'][$delta] . '&gt;' . drupal_render($item) . '&lt;/li&gt;';
    }
    $output .= '&lt;/ul&gt;';

    // Render the top-level DIV.
    $output = '&lt;div class=&quot;' . $variables['classes'] . (!in_array('clearfix', $variables['classes_array']) ? ' clearfix' : '') . '&quot;' . $variables['attributes'] .'&gt;' . $output . '&lt;/div&gt;';

    return $output;
  }
}

Once implemented, try flushing you theme cache, it should work.