A simplex-centroid mixture design was used to study the effect of solvent composition (acetone, methanol, water and ethanol) on the extraction of total monomeric anthocyanins (TMA) and total phenolic compounds (TPC) content from freeze-dried açaí pulp (Euterpe oleracea Mart.). Next, the effect of time, solid-to-liquid ratio (S/L) and HCl concentration on these responses was investigated through a central composite design (CCD). Finally, the number of re-extractions (n=3) to achieve maximum extraction yields was examined. As the composition of the extractor solvent changed, TPC and TMA varied from 5.23 to 24.81 mg.g-¹ and from 0.15 to 4.14 mg.g-¹, respectively, suggesting that the solvent composition affected the extraction of the compounds studied. The simplex-centroid design indicated significant synergistic effect of binary and ternary solvents, methanol and acetone mainly contributing for increasing extraction efficiency. Acetone:methanol:water (31:24:45 v/v/v) 0.1% HCl was chosen as the best solvent. Regarding the CCD, minimal values were higher than those from the mixture design, ranging from 13.98 to 28.98 mg GAE.g-¹ and 1.36 and 3.06 mg.g-¹ for TPC and TMA, respectively. This result indicates that varying extraction parameters other than solvent composition might also affect extraction efficiency. TMA concentration has not been affected by none of the variables considered, whereas TPC content raised with time up to 9 minutes, and started to decrease thereafter. Moreover, S/L had a significant negative interaction effect with time, indicating that by using low S/L, extraction times can be shortened. Then, optimal conditions were: half a gram of freeze-dried sample, S/L 1:54 of acetone:methanol:water (31:24:45 v/v/v) 0.1% HCl and sonicated for 6 minutes. Finally, results indicated that two extraction (n=2) succeeded in extracting 99% and 83% of TPC and TMA, respectively, confirming that multivariate optimization tools are effective to give extraction protocols for saving time, reducing costs and use of toxic solvents.