The purpose of this study was to evaluate the effect of three different retention forms on the bond strength when complete denture repaired. Total 75 samples were divided into 3 groups(Dove-tail form, bevel form, rabbit form). The completed resin samples were compressed in Instron Testing Machine until gross fracture occurred to examine the effect on the bond strength of resin base. The results of the experiment were as follows : 1. The difference of bond strength according to three retention forms were not statistically significant(P>0.05). 2. Dove-tail form was strongest to bond strength among the three retention forms.