Problems experienced by some people who have never assemblied computer is the difficulty of understanding computer components and assemblying computer. This is because assembling computer carelessly might damaged the computer’s component that cost relative expensive. The existence of computer assembly simulation will help people who have difficulty to assamble computer especially for beginner and intermediate users. With this problem, this research aims to develop simulation application to assemble computer for android user in order to increase user understanding in recognizing computer hardware component and to provide experience to install computer component without buying or having original component, especially for beginner and intermediate user. The results showed that the user's ability to recognize components and assembly tends to increase after using the Computer Assemble application, rather than before using. This is evidenced by the significance value of 2-tailed (p) on the Paired T test test of < 0.001 which means there is a real difference between before using the application and after using the computer assembly simulation application.