The power of mathematics lies in relations and transformation which give rise to patterns and generalizations. Pattern was prevalent at all levels of mathematical endeavour when children were at the kindergarten level up to junior high school level. Students learned variety of patterns such as repeating patterns and growing patterns. Pattern exploration might contribute to the development of problem solving skill through emphasis on case-spesific analysis, organising data in systematic way, conjecturing, and generalizing. In terms of pattern generalization, students could draw conclusions that depend on the student’s understanding or concepts and how they could be done to generalize them. The purpose of this study was to describe the process of generalizing the pattern of junior high school students in solving phase. This research used qualitative research that produced descriptive data. Subject in this research were 3 students with different mathematical abilities. Data collection technique were conducted with problem solving task and task-based interviews. Based on the result of the research, the process of generalization of junior high school student’s pattern in solving mathematical problems by students of high, medium, and low math abilities were variety especially in the planning and execution phase.