Objective To address the instability of anthocyanins in dragon fruit beverages due to fermentation factors a fermentation process was optimized to develop a refreshing flavorful dragon fruit beverage rich in anthocyanins and with strong antioxidant capacity. Methods Red-fleshed dragon fruit was used as the raw material with Lactobacillus plantarum and Streptococcus thermophilus as fermentation agents. Based on single-factor experiments the initial pH of the fermentation broth inoculum volume of the seed solution and fermentation time were selected as influencing factors while the anthocyanin content of the fermented dragon fruit beverage served as the response value. Response surface methodology was employed to determine the optimal process parameters. The anthocyanin content soluble solid content, and DPPH radical scavenging rate were measured before and after fermentation to evaluate the effect of the fermentation process on the antioxidant activity of the beverage. Results The optimal fermentation conditions were as follows inoculum volume of the seed solution of 1. 7% initial pH of 6. 3 and fermentation time of 24 hours. Under these conditions the fermented dragon fruit beverage exhibited natural clarity stable texture and distinct dragon fruit aroma with fermented notes. The anthocyanin content was 50. 10 ± 0. 28 mg / L which was only 11. 68 mg / L lower than that of the unfermented dragon fruit juice. The DPPH free radical scavenging rate was significantly increased and the content of anthocyanin and soluble solids did not change much. Conclusion The fermentation process preserved the nutritional components of the dragon fruit beverage while enhancing its antioxidant capacity. These findings provide valuable insights for enriching the fruit and vegetable fermented beverage market in China.