Abstract: Basic principle and procedure in standard ASTM E23-2007“Standard Test Methods for Notched Bar Impact Testing of Metallic Materials” were described. Appraisal for pendulum impact machine including direct appraisal and indirect appraisal was introduced,and parts of direct appraisal and requirements of standard specimens for indirect appraisal were given. When both of the two parts were acceptable,the Charpy impact machine was acceptable.