Method of impact test for composite resins was investigated according to JIS K 7110, "Method of Izod impact test for rigid plastics". The following views were suggested from the results of the experiments. 1) For the heterogeneous paste-type materials such as composite resins, the test specimens should be prepared with a metal mold that can add the V-notch to a test piece on polymerization process, rather than mechanically done with frise cutter. 2) On the testing according to JIS K 7110, sample could not be saved in large amount against our expectation. Therefore, it may be necessary to develop the testing machine that has a smaller capacity.