Competency-based teaching model is an important aspect in increasing students achievement. By using this model, the quality of teaching and learning process can be improved. In teaching chemistry, competency-based teaching model is more stressed on basic competencies the students should have. The students have to comprehend the main concept or principles if chemistry subject matters. The problem is what kind of competency-based teaching model that is appropriate for use in increasing students achievement. This research develops and investigate four models of competency-based teaching, such as competency-based teaching models of concept attainment, problem solving, inquiry training and cooperative learning approach. The research was carried out on 40 students for each class I,II dan II SMA Negeri 5 Padang. The result of the study showed that the implementation of four teaching models can increase students a achievement in chemistry subject. It can be concluded that the implementations of competency-based teaching model can improve students achievement at secondary High School.