A novel heated tip multi-hole spark ignition direct injection (SIDI) injector was designed and manufactured to research its coupling mechanism of the multi-physical fields and comprehensive performances. In order to realize the multi-physical fields coupling simulation, the coupling relationship and coupling formation among the electromagnetic, thermal, fluid flow and spray fields were analyzed based on coupling theories. The data information interface platform based on the commercial software was used to calculate the key parameters of the novel SIDI injector. The simulation data transfer and output mechanism were analyzed and the coupling models based on finite element method (FEM) were established to analyze the comprehensive performances systematically. The systematic experiments were utilized to validate and verify coupling mechanism and the accuracy of the simulation model. Compared to the conversional SIDI injector, the novel heated tip SIDI injector can heat the fuel and cause the temperature rising in a short time. In order to investigate the relationship between the temperature and performances of the injector, the multi-physical fields coupling analysis of the novel heated tip SIDI injector were done by simulation and experiments. According to the systematical analysis of the multi-physical fields of the novel heated tip SIDI injector, it was found that the heat generate from the heater and magnetic circuit is the most significant factor that influence on the electromagnetic, fluid flow and spray.