It is a very important phase in resin transfer molding (RTM) process that resin is cured. The result of the curing process determines the quality of a part, including mechanical properties, lifecycle of the part under high temperature and chemical properties. Therefore, it is very meaningful to discuss the curing process. In our work, the code is prepared based on unstructured mesh using divergence theorem. A case is used to verify properness of the code and the results are in good agreement with the published experiment data. In the paper, some factors of materials and numerical calculation, e.g., time step, reaction heat, the whole heat conductivity of fiber and resin and fiber initial temperature, which affect result of simulation, are emphatically investigated and carefully revealed. The conclusion shows that time step, the reaction heat and heat conductivity have an important effect on the curing process, while fiber initial temperature has very little impact. These are helpful to understand and adopt the curing process in order to produce good products.