<meta property="fb:admins" content="[Your FB app ID]" />  
  
<!-- if page is content page -->  
<?php if (is_single()) { ?>  
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>	 
<meta property="og:url" content="<?php the_permalink() ?>"/>  
<meta property="og:title" content="<?php single_post_title(''); ?>" />  
<meta property="og:description" content="<?php echo strip_tags(get_the_excerpt($post->ID)); ?>" />  
<meta property="og:type" content="article" />  
<?php endwhile; else: endif; ?>  
<!-- if page is others -->  
<?php } else { ?>  
<meta property="og:site_name" content="<?php bloginfo('name'); ?>" />  
<meta property="og:description" content="<?php bloginfo('description'); ?>" />  
<meta property="og:type" content="website" />  
<?php } ?>

To be used in the header.php

Facebook OpenGraph tags for a Wordpress site

wordpress, facebook

PHP