This study aimed to investigate the relationship between self-regulation, free time management, and self-esteem variables among high school students. The research sample consisted of 193 girls and 276 boys, totaling 469 students studying in different types of high schools. The Personal Information Form, the Adolescent Self-Regulatory Inventory, the Free Time Management Scale, and the Two-Dimensional Self-Esteem Scale were used to collect data. Independent samples t-test analysis was conducted to compare the self-regulation, free time management, and self-esteem scores of the students in terms of gender and status of doing sports. One-way analysis of variance (ANOVA) was performed to compare the scores based on grade level, type of high school, and types of leisure time activities. In addition, correlation analysis was conducted to test whether there is a relationship between self-regulation, free time management, and self-esteem scores of the students. The results of the analyses indicated that there was a significant difference in self-regulation scores among the students based on gender, while no significant difference was found in free time management and self-esteem scores. However, significant differences were found in self-regulation, free time management, and self-esteem scores based on the status of doing sports. There was a significant difference in self-regulation scores according to grade level, while no significant differences were found in free time management and self-esteem scores. A significant difference was found in self-regulation and free time management scores based on the type of high school, but no significant difference was found in self-esteem scores. When examined in terms of leisure time activity type, significant differences were found in self-regulation, free time management, and self-esteem scores. The grade point averages of the students showed a negative correlation with their daily average free time, yet a positive correlation with their self-regulation scores. Self-regulation scores were found to be positively related to free time management and self-esteem scores. In conclusion, it is believed that the exploration of the relationships between high school students' grade point averages, free time, self-regulation skills, free time management, and self-esteem scores may play a significant role in helping high school students achieve positive outcomes.