For comparing the impact of Simple and Combined Process-and-Outcome of mental simulations on the educational performance and achievement of talented and normal students involved in it, experimental method were used. The results would be used in developing curriculum and educational methods.104 talented students and 104 normal students were chosen in a target sampling from the first-grade female students and were located in a random sampling in three groups of Process, Outcome and Combined mental simulations and a fourth control group.The research question was, whether or not the impacts of Simple and Process-and-Outcome Combined mental simulations were different among the normal and talented students. First, Educational Performance Test and the mid-term exam of chemistry were given to all the subjects. Then for five to ten-minute sessions, mental simulations were taught to the experimental groups with the control group receiving no instructions. At the end of the term, Educational Performance Test and final exam of chemistry were given to the subjects. The data were analyzed by using the following statistical methods: multiple analysis of variance (Manova), Multiple analysis of Co-variance (Mancova), Analysis of Co-variance, one-way anova and Post Hoc Test (Tuckey), based on distinguishing points. The results showed that mental simulations were effective in educational performance, and in its improvement, but weren’t effective in the educational achievement. Intelligence, as a moderating variable, didn’t have any impact on the relation between mental simulation and educational performance. In the case of talented students, Outcome mental simulation was the main cause of educational performance. In the normal students, however, process mental simulation was more efficient than other simulations.