The aim of this study was to investigation of the relationship between knee and ankle angles and squat/countermovement jump heights at the age group of 15-17 swimmers. 10 girls (mean age 15.30±0.48yrs, mean height 165.00±5.33cm, mean mass 49.60±5.10kg) and 13 boys (mean age 16.00±1.00yrs, mean height 178.00±7.32cm, mean mass 64.31±7.35kg) were participated to this study as voluntarily. 10min dynamic dryland warming time were given and after that reflective markers were placed on the lower extremity joints. The wand calibration method was used for calibrated to the area. Fusion Sport Smart Jump matt was located in the area to calculated swimmers' jump heights. Swimmers performed three squat jump (SJ) and countermovement jump (CMJ) trials which were recorded at a frequency of 120Hz using seven high-speed cameras (Oqus 7+). The results were analyzed by Qualisys Track Manager program. Both knee and ankle angles and jump heights relations were calculated. Pearson Correlation and Mann Whitney-U was used in SPSS 21.0 program for analysed. There were no significant relations between SJ and CMJ performances and angles (p>0.05). There were significant differences between boys and girls in both jump heights (p<0.05). For correct jump performance, it is recommended to position the joints according to the recommended optimal angular values. [Note: The publication year (2022) shown on the PDF is incorrect. The correct publication year for this article is 2023.]