Level of sales in the automotive field especially car had increased. In the consumer car buying decision would be influenced by external and internal factors. One of the factors that influence consumer behavior in making purchasing decision is an internal factor that is composed of consumers of psychological motivation, perception, learning and attitudes, therefore it is expected the company to better understand consumers' psychological factors. The purpose of this research is to know how big the influence of psychological factors on consumer decision making in buying Mitsubishi Pajero Sport. The hypothesis in this study there were four. First, motivation significantly influence on Pajero Sport purchase decisions. Second, perception significantly influence on Pajero Sport purchase decisions. Third, learning significantly influence on Pajero Sport purchase decisions. Fourth, attitude significantly influence on Pajero Sport purchase decisions. The study was conducted by distributing questionnaires to the owners of Pajero Sport in March 2011 and given priority in West Jakarta. Measurement scale used is a modification of the Likert scale with judgemental sampling technique. The data that have been collected are then tested with validity and reliability test, and also regression testing conducted on the psychological factors that influence purchasing decisions. The results illustrate that the psychological factors of motivation (X1), perception (X2), learning (X3), and attitude (X4) collectively or partially have significant influence on purchasing decisions (Y) based on f and t test results. Then from the adjusted R2 value can be seen that the regression equation model in this study are influenced by motivation, perception, learning and attitudes can be used to predict Pajero Sport purchasing decisions at 61.3%.