The main control room is the place where the control operation of a nuclear power plant is carried out under normal and accident conditions. It is necessary to evaluate the radiation dose of workers in the main control room to ensure the habitability of the main control room under accident conditions. Current analysis models typically use the source term released into the environment as input. These source terms are divided according to the atmospheric dispersion factors of the main control room and are released linearly over the corresponding time segment. However, the actual transient radioactivity release rate to the environment under different accident conditions has not been considered. This paper studies the effect of the source term release rate on the dose evaluation of workers in the main control room. Different source term release rates based on specific accident scenarios have been considered, including instantaneous release, linear release, and large early release during the accident. The coupling analysis of the environmental source term release rate and the radiation dose of workers in the main control room is conducted. The results of this study provide an accurate and realistic assessment of the radiation dose of workers in the main control room under accident conditions.