<?php $recent_comments = get_comments('status=approve&number=5'); ?>
          <?php foreach ($recent_comments as $comment) { ?>
            <li>
                <a href="#"><?php echo get_avatar( $comment, '60' ); ?> </a>
                <div>
                    <a href="<?php echo get_permalink($comment->comment_post_ID); ?>" title="on <?php echo get_the_title($comment->comment_post_ID); ?>"><?php echo strip_tags($comment->comment_author); ?>   </a><br />
                    <span><?php echo wp_html_excerpt( $comment->comment_content, 35 ); ?>...</span>
                </div>

            </li>
        <?php }  ?>

Try this code , you have not used the correct output variables.

<?php $recent_comments = get_comments('status=approve&number=5'); ?>
          <?php foreach ($recent_comments as $comment) { ?>
            <li>
                <a href="#"><?php echo get_avatar( $comment, '60' ); ?> </a>
                <div>
                    <a href="<?php echo get_permalink($comment->comment_post_ID); ?>" title="on <?php echo get_the_title($comment->comment_post_ID); ?>"><?php echo strip_tags($comment->comment_author); ?>   </a><br />
                    <span><?php echo wp_html_excerpt( $comment->comment_content, 35 ); ?>...</span>
                </div>

            </li>
        <?php }  ?>