BuddyPress.org

Hi gian-ava . Try this assuming your active link is .active

<li<?php if ( bp_is_front_page() ) : ?> class="active"<?php endif; ?>>

<a href="<?php echo site_url() ?>" title="<?php _e( 'Home', 'buddypress' ) ?>"><?php _e( 'Home', 'buddypress' ) ?></a>

</li>