<p>This article describes application of 4C (Critical, Creative, Communicative, and Collaborative) in Calculus learning to improve students' ability to solve mathematical problems. This research was classroom action research. Subjects of this study were students of IKIP Budi Utomo Malang Mathematics Education program. Steps of 4C learning that can improve problem solving skills were (1) students were given problems that encourage critical and creative thinking, (2) they were asked to collaborate and communicate in groups, (3) demonstration activities that require each student to communicate in front of classmates, (4) students asked to make problems that encourage creative thinking. Results of the study indicate that there was an increase in student’s ability to solve problems after being given 4C learning. In the preliminary study, most students were able to understand problem, but few students were able to make plan and implement plan. In the first cycle, for stage of understanding problem obtained an average score more than 70, but the other stage less than 70. Because in the first cycle did not fulfill the criteria for success, the second cycle was carried out. In the second cycle research, the average score of each stage more than 70 with details for stage of understanding problem 88, implementing plan 76, and looking back 75. So 4C learning can improve student problem solving skills.</p>