The objective of this work was to optimize extraction process and to validate the HPLC-DAD method for quantification of ascorbic acid content in mixed juice powder of acerola and seriguela with different dextrose equivalent maltodextrin (5, 10, 15) as an encapsulating agent. The influence of the extraction variables was studied through factorial design. Control variables were mass, percent of orthophosphoric acid and stirring time. Chromatographic method was validated in terms of precision, selectivity, linearity and accuracy. Chromatographic and titrimetry results were compared for all dextrose equivalent. Mass and percentage of orthophosphoric acid presented p < 0.05. There were no significant differences among the dextrose equivalents ranging from 2,830.1 mg/100 g to 2,931.61 mg/100 g of ascorbic acid. Both values, intra and intermediary precision test coefficients of variation were less than 5%. The correlation coefficient was 0.99. Respective value of limit of detection was 0.001 mg/mL and for quantification was 0.003 mg/mL. The application of HPLC-DAD method can be considered acceptable for quantification ascorbic acid in fruit powder.