The objective of this study was the determine the chemical composition, amino acids profile, limiting amino acids, sodium dodecyl sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE), In-vitro digestibility, and functional properties of quinoa flour (QF) and protein isolates (PI). QF contains significant amounts of protein, fat, fiber, ash, and carbohydrates 14.25, 7.00, 5.14, 3.16,and 70.45%, respectively. Purity of PI was 94.12%, and impurities were about 6%. The first limiting amino acid in QF is cysteine, the second is methionine, and the third is proline. In contrast, in PI the first amino acid is cysteine, the second is histidine, and the third is methionine. The efficiency ratio of quinoa flour proteins (QFP) is higher than that of the PI. The molecular weight (MW) of QFP and PI have similar MW (250,130, 100, 70, 55, 35, and 25 K Da). QFP showed higher digestibility than PI (84.13%, and 79.51%, respectively). QF had a higher significant (P ≤ 0.05) water absorption capacity than PI. The fat absorption capacity was 1.38 gm oil /gm of flour for defatted quinoa flour and 1.98 gm oil /gram of protein isolates. We foundnd that quinoa protein has a high foam stability within 60 min.