One of the causes of students' low higher level thinking abilities is the use of teaching strategies. This research aims to investigate the role of higher order thinking skills teaching strategies to improve students' critical thinking skills in science learning. The research design used was quasi-experimental by dividing students into three groups, namely the experimental class which received teaching strategy intervention that encouraged higher level thinking skills, while the other two groups were students majoring in science and non-science who received traditional teaching intervention. The participants involved were 300 vocational school students. The instruments used in this research are critical thinking skills assessment instruments, dispositions observation sheet of teaching strategies used by the teacher, and question sheets that reveal the teacher's perspective on higher order thinking skills. Quantitative analysis was applied to the data and included descriptive statistics and ANOVA tests and was strengthened by qualitative data analysis using analysis of interview results. Research findings show that students in the experimental group showed significant improvements in all components of critical thinking and dispositional aspects. The increase in critical thinking skills appears significant in all aspects, namely evaluative, identification and inference. Improvements in the disposition aspect can be seen in the ability to seek the truth, the ability to open one's mind, self-confidence, and maturity in facing problems. In addition, teaching designed to improve high-level thinking skills has intensity in several activities such as always presenting problems in context, open discussions, encouraging students to experiment, being inquiry-oriented, and providing many opportunities to develop critical thinking skills. This research means that students' critical thinking abilities can be improved by designing teaching that integrates several methods that encourage them to think critically. Researchers recommend the need for teacher professional development programs, especially in the use of teaching strategies that encourage higher order thinking skills in the teaching process.