Abstract: Broad bean seeds are a rich source of protein.The limited hydrolysis of broad bean proteins used Metrohm 808 automatic titrator aiming at the problems of low solubility of broad bean protein at low pH.Functional properties of native and modified (through limited enzymatic hydrolysis) broad bean had been investigated.Broad bean hydrolysates with 2.0% to 4.0% degree of hydrolysis (DH) were produced by papain.Compared with native broad bean protein, the protein solubility was improved 4.0～5.0 times in the range of pH4.0～6.0.The limited proteolysis isolate had better emulsifying and foaming properties than the native isolates, emulsifying capacity and the water-holding capacity of modified protein was increased 2.3 and 1.6 times at pH 6.0, respectively.