For interconnection network losing processors, it is considerable to calculate the number of vertices in the maximal component in the surviving network. Moreover, the component connectivity is a significant indicator for reliability of a network in the presence of failing processors. In this article, we first prove that when a set $M$ of at most $3n-7$ processors is deleted from an $n$ -star graph, the surviving graph has a large component of size greater or equal to $n!-|M|-3$ . We then prove that when a set $M$ of at most $4n-9$ processors is deleted from an $n$ -star graph, the surviving graph has a large component of size greater or equal to $n!-|M|-5$ . Finally, we also calculate the $r$ -component connectivity of the $n$ -star graph for $2\leq r\leq 5$ .