This study aims to (1) determine the difference between the improvement in students' self-regulation skills before and after the implementation of the GITTW learning strategy, and (2) describe students' perception of the skills of selfregulation before and after the implementation of the GITTW learning strategy. This is pre-experimental research using a one-group pre-test-post-test design. The population was made up entirely of students in their sixth semester at the Biology Education department who programmed the Physiology Anatomy of Human Body course in the 2017/2018 academic year in the Teacher Training and Education Faculty at University of Muhammadiyah Surabaya, Indonesia. The samples comprised of 20 students from one class. The data of students' self-regulation skills were obtained from the score of an essay test and inventory method. The data were analysed using descriptive and inferential statistics with the N-gain test. The results showed that the students' self-regulation skills improved after the implementation of the GITTW learning strategy. This can be seen from the average pre-test score of 36.2, the post-test score of 74, the average gain of 37.8 and the average N-gain of 0.60 included in the medium category. The average inventory self-regulation skills score before the implementation of the GITTW learning strategy reached 76.57%, including the strong category, and after it reached 80%, including the very strong category.