The amino acid retention with an alumina gamma nanofiltration membrane was investigated. Research was conducted on the effect of various experimental parameters such as transmembrane pressure, salt concentration and pH on the experimental retention coefficient (R-o) of mineral nanofiltration membrane. Four different amino acids (2 neutral, 1 acidic and 1 basic) were used as solutes in NaCl (0.1 M), The behaviour of each was determined alone and in a mixture of the four amino acids. Comparison of the experimental retention coefficient and the size retention coefficient indicates that charge effects facilitate rejection of the amino acids by alumina membrane. It was demonstrated that nanofiltration of amino acids is strongly influenced by solute environment and by hydrodynamic parameters.