Critical thinking skills is one of 21st century skill. This requires students to solve the problems they face. Therefore, it need a test instrument that can assess students' critical thinking skills. This study aims to develop instrument test of critical thinking skills of high school students by two tiers test format related to temperature and heat concept. The research method used was the ADDIE development model (Analyze, Design, Development, Implementation and Evaluation) conducted by 11th grade high school students who have studied temperature and heat concept. The number of respondents of research as many as 30 students in 11 grade senior high school in Bandung. Data collection using the Halpern framework critical thinking skill instrument test adapted by Tiruneh by two tiers test format. The results obtained that the test instrument of critical thinking skills related to temperature and heat concept by two tier test format can assess students' critical thinking skills. Thus, the development of critical thinking skill test by two tier test format has the potential to be one of the test instrument for assessing and trained students' thinking skill.