Background: Various fillers have been used for the correction of nasolabial folds. This study investigated the efficacy and safety assessment of two hyaluronic acid (HA) fillers on moderate nasolabial folds. Methods: This study randomized 10 volunteers, aged 35 to 49 years, with moderate nasolabial folds. Volunteers received injections of HA A and HA B gels into the right or left skin folds. The volume and surface of nasolabial folds were analyzed using CSI computer software and high frequency ultrasonography of these folds before, and 2, 12, and 24 weeks after the injection. The obtained data were analyzed using SPSS software version 20. P≤0.05 was considered significant. Results: Evaluation of the nasolabial folds before and after treatment showed significant reduction in volume of wrinkles 24 weeks after injection in both the HA gel A (-29.93±32%, P=0.022) and gel B (-23.60±26%, P=0.019). The surfaces of the wrinkles significantly decreased 24 weeks after injection of HA gel A (-29.90±31%, P=0.012) and gel B (-21.96±26%, P=0.026). Conclusion: These HA fillers provided a significant, long-lasting correction of moderate nasolabial folds. Overall, we observed no statistically significant differences in any of the measurements between the 2 gels. However, there were more observed changes made by gel A compared to gel B.