i have to link the lasts 5 posts of the identical category following the publish content in wordpress. Anybody might help me? thanks

You can aquire anithing you would like using WP_Query. It's very flexible and you ought to certainly begin using it. It is similar to the SQL queryes.

Prior to the loop declare some var which will hold publish category. Than query posts with this cat.

Here's example:

<?php
$cat_id = 0; // declare var
if(have_posts()):
  while(have_posts()):
    // do what you usually do
    $cat_id = $post->post_category;
  endwhile;
endif;

// here you will get posts and make html output
$last_in_cat = get_posts('posts_per_page=5&cat='.$cat_id);
foreach($last_in_cat as $cat_post):
?>
<a href="<?php $cat_post->guid ?>"><?php $cat_post->post_title ?></a>
<?php endforeach; ?>