In　order　to　achieve　the　packages　with　much　higher　performance,　more　IIOs,　lower　profile　and　lighter　weight,　the　thickness　of　silicon　wafer　has　been　decreased　dramatically　in　recent　years,　but　which　degrades　the　strength　of　thinned　wafer.　In　this　paper,　three-　point　bending　test　was　adopted　to　evaluate　the　thinned　wafer　fracture　strength,　and　the　impacts　of　back-　grinding　process　parameters　on　the　wafer　fracture　strength　were　addressed.　Results　show　the　trend　of　an　increase　in　wafer　strength　with　an　increase　in　grinding　wheel　rotational　speed　and　a　decrease　in　grinding　wheel　feed　rate.　Also,　it　is　found　that　the　strength　decreases　progressively　from　the　center　of　wafer　to　the　edge　for　most　wafer　samples.