This study aims to describe the cognitive processes of junior high school students with high mathematics skills in solving the word problem on fraction. The cognitive process is the activity of processing information in one's mind. Information processing involves receiving, processing, storing and retrieving information. The subjects of this research were two students, a female and a male student. The subjects were given problem solving task and in-depth interviews. To get valid data, triangulation time is done by giving equivalent task and interview at different times. The results showed that there was a difference of cognitive processes from both students that started from information processing when planning problem solving. Female students used rectangular diagrams with computations using visual comparisons, while male students used arithmetic computations.