This research is motivated by the results of previous studies that showed that students' mathematical problem solving ability is not as expected. One lesson to improve mathematical problem solving is based learning problems . The purpose of this study was to determine the increase in students' mathematical problem solving ability as a result of problem-based learning. This study is a quasi-experimental study that applies two problem-based learning and conventional learning. The population in this study were students in one of the vocational schools in Garut. Sampling was done by purposive sampling, and obtained two classes as the study sample. The research instrument used was a test of mathematical problem solving abilities. Based on these results we concluded that: (1) the increase in students' mathematical problem solving ability that gets problem-based learning better than students who received conventional learning, (2) mistakes made by student when working on the problems related to mathematical problem solving ability was a mistake due to carelessness or less closely, tansform fault information, error process skills, and misunderstanding question.
Keywords: problem based learning, mathematical problem solving abilit
