In this double-blind, placebo-controlled clinical study, we investigated the efficacy of specific bioactive collagen peptides (BCP) on the cellulite treatment of normal and overweight women. In total, 105 women aged 24–50 years with moderate cellulite were randomized to orally receive a daily dosage of 2.5 g BCP or a placebo over 6 months. The degree of cellulite was evaluated before starting the treatment and after 3 and 6 months of intake. In addition, skin waviness, dermal density, and the length of subcutaneous borderline were assessed. BCP treatment led to a statistically significant decrease in the degree of cellulite and a reduced skin waviness on thighs (P < 0.05) in normal weight women. Moreover, dermal density was significantly improved (P < 0.05) compared to placebo. The subcutaneous borderline showed a significant shortening after BCP intake compared to the beginning of the study, indicating cellulite improvement, but the data failed to reach statistical significance compared to placebo. The efficacy of BCP treatment was also confirmed in overweight women, although the impact was less pronounced in comparison with women of normal body weight. The results of the study demonstrated that a regular ingestion of BCP over a period of 6 months led to a clear improvement of the skin appearance in women suffering from moderate cellulite. Based on the current data, it can be concluded that a long-term therapy with orally administered BCP leads to an improvement of cellulite and has a positive impact on skin health.