A comparative study between two widely used software process improvement mechanisms, CMMI(Capability Maturity Model Integrated)and ASPICE(Automotive Software Process Improvement and Capability dEtermination), was described in this paper. The document analysis method was used to collect, manage and classify the reference materials. Based on the comparative research method, 5 points including model, structure, level, process area and evaluation method were juxtaposed and analyzed. Furthermore, the vehicle electronics industry was applied as a case study for the difference analysis of both implementation and output. We hope it can be a reference for the industry companies to employ the certification of software process improvement.