This study aims to examine the effects of high-intensity interval training (HIIT) on body composition and lipid profile levels. The study was conducted with 24 male professional football players. The participants were randomly divided into two equal groups, which included 12 individuals in the control group and 12 individuals in the training group. The participants in the control group were not involved in any training program while the participants in the training group regularly participated in an 8-week long HIIT conducted 3 days a weak. Before and after the study, all the participants were examined for body weight, body mass index (BMI), heart rate, and blood samples. The blood samples were evaluated in terms of triglyceride, low-density lipoprotein (LDL), highdensity lipoprotein (HDL), and cholesterol levels. In the data analysis, SPSS package software was used, and the level of statistical significance was regarded as p<0.05. As a result of the study, statistically significant differences were observed in resting heart rate, BMI, and body weight levels according to intragroup pre and post-test results of the training group, and the post-test results of training and control groups (p<0.05). On the other hand, there was no statistically significant difference in the intragroup pre and post-test results of the control group (p>0.05). Furthermore, no statistically significant difference was observed in the triglyceride, LDL, HDL, and cholesterol levels between the intragroup pre and post-test results of the participants in the training and control groups (p>0.05) while statistically significant differences were observed in the triglyceride levels according to the post-test results of training and control groups (p<0.05). High-intensity interval training provides significant improvements in resting heart rate, BMI, body weight, and triglyceride levels.