In this study, natural pigments from Basella rubra L. were extracted by ultrasound-assisted extraction (UAE) technique using three levels, four factors (extraction temperature, ultrasonic power, extraction time and solid-liquid (SL) ratio) Box-Behnken response surface design. The optimal condition was found to be: extraction temperature of 54 degrees C, ultrasonic power of 94 W, extraction time of 32 min and SL ratio of 1:17 g/mL respectively. Under this optimal condition, the experimental yield of (betacyanin of 1.42 +/- 0.001 and betaxanthin of 5.35 +/- 0.13 mg/g) pigments were well correlated with predicted values (betacyanin was 1.43 mg/g and betaxanthin was 5.37 mg/g).