Students use self-regulated learning, a self-directed process, to evaluate their learning as they work toward academic objectives. This study aims to determine the degree of self-regulated learning strategy in a flexible learning environment with regard to affective, cognitive, metacognitive, and motivational strategy; ascertain the level of students’ academic performance in flexible learning; assess if there is a significant relationship between the students’ academic performance and the self-regulated learning strategies; and find out which variable, singly or in combination, predicts students’ academic performance. The study used a descriptive quantitative correlational design. The study is conducted at Valencia National High School, Valencia City, Bukidnon. The research respondents were 150 Grade 10 students. The reseachers used descriptive statistics to determine the level of each sub-variable of self-regulated learning strategies and the students’ academic performance. The relationship involving self-regulated learning and students' mathematical performance is examined using Pearson Product Moment Correlation. Finally, to predict which sub-variables predict students’ academic performance, it utilizes regression analysis. Results showed that students are indicated positive about self-regulated learning. The student's academic performance is rated as very satisfactory. Henceforth, there is a significant correlation between students' academic performance and their use of a self-regulated learning strategy. Lastly, the sub-variable that predicts students’ academic performance is the metacognitive strategy.