There exists an important relationship between the temperature fields and the heat utilization efficiency in the oven of rotational molding equipment. If the temperatures at the main locations can be reasonably controlled, then the efficiency of the rotational molding machine can be effectively improved. The main objective of this research project is to carry out numerical simulation and analysis of the velocity field and temperature field in the oven of a shuttle-type rotational molding machine by using the commercial code FLUENT. The machine was selected as the research object owing to its uneven temperature fields and large energy wastage. The simulation results were then verified by experiments. By improving the structure of the outlets of rotational molding machine and by reasonably controlling the temperature distribution in the oven and die, the working temperature can quickly reach the maximum point, and the uniformity of the temperature in the working area can be ensured. The results showed that the molding efficiency and energy efficiency of the rotational molding machine can be improved by controlling the temperature distribution, thereby increasing the production efficiency of rotational molding.