This aim of study is to obtain an overview of the improvement decision-making skill of senior high school students as the effect of applying dilemmatic problem solving oriented learning model in physics teaching. The research method used is pre-experiment with one group pretest-posttest design. The subjects of the study were 38 students in one of the high schools in West Bandung district. The subjects were chosen by random sampling technique. Instruments used for decision-making skill data collection at before and after learning is a test of decision-making skills in the form of essay test. The improvement of decision-making skills of high school students was analyzed using the concept of normalized average gain scores, <g> formulated by Hake. The results showed that 58% of students reach a high gain, 29% of students reach a moderate gain and 13% reach a low gain in decision-making skills. This shows that the use of dilemmatic problem solving-oriented learning model in Physics learning has a moderate effectiveness in facilitating the improvement of decision-making skill of high school students.