In this study, we tried to evaluate the mechanical properties of Polycarbonate(PC) and acrylonitrile-butadiene-styrene(ABS) plastic materials, which are frequently used as parts of home appliances and machinery, when repeated impacts were applied. A repeating impact tester for this research was designed and manufactured to apply repetitive impacts. Two types of plastic were repeatedly impacted under a constant load, and a tensile test was performed on the plastic material that was impacted. The tensile strength of PC plastic materials that received impact more than 2000 times was reduced by about 45 % and elongation was reduced by about 10 % when compared to impact free specimens. On the other hand, in ABS plastic, a reduction of tensile strength of about 20 % was observed at about 2,000 impacted specimen, but at about 20,000 repetitive impacted specimen, a tensile strength decrease of about 65 % was observed. And the elongation was reduced by 10 % due to the cyclic harding behavior of the material.