This study is about the development of information system software process quality evaluation model for domestic medium enterprises based on CMMI being used widely in the world. In this study, a new evaluation model is developed through establishing tailoring guide and its application to the existing mode by reflecting the quality management method and conditions of domestic medium enterprises within CMMI Level 2 and Level 3. The evaluation model is constituted 3 processes, 11 achievement goals, 50 practice activities and 125 evaluation items. The average point of quality evaluation of enterprises of insurance business shows 79.1 based on the evaluation model. The average point of the enterprises certified from CMMI is 82.7 which is 3.3 point higher than non-certified enterprises. This result means that the new evaluation model has similar results with the existing evaluation model while it also has discriminational characteristics compared with the existing model.