This study assessed differences in knee joint range of movement (ROM) and the Leg Symmetry Index (LSI) during four tasks in healthy athletes (n = 15). We hypothesized that there would be no significant differences in the ROM and LSI of the knee in the sagittal plane in elite athletes when performing squats, lunges, single-leg landing drop, and drop vertical jump. Fifteen athletes (14 males) performed each task. Knee kinematics were recorded using a six-camera motion capture system. Seventeen reflective markers were placed bilaterally to calculate angular trajectories of the knee joint, and vectors from femur and fibula landmarks were used to quantify the ROM of the knee in a sagittal plane. Differences in ROM between the dominant leg (DML) and non-dominant leg (N-DML) were analyzed using paired t-tests, while LSI was computed as the N-DML/DML ratio. One-way ANOVA was used to compare LSI across the four tasks. Results showed no significant differences in ROM between limbs in any task (p > 0.05). LSI values were consistently close to 1.0, indicating high inter-limb symmetry. No significant variation in LSI was found between tasks (p = 0.992). These findings suggest that healthy athletes exhibit symmetrical knee ROM and LSI across diverse dynamic tasks, providing relevant benchmarks for injury prevention and functional assessment.