Legume seed proteins have received attention during recent years owing to their higher biological values and better functional properties than oilseed proteins. In present study, protein isolate extraction from Chickpea (CPI) and Lathyrus sativus (LPI) seeds was optimized using response surface methodology. Also, influences of protein extraction methods on physicochemical and functional properties of protein isolates such as oil absorption capacities, water absorption capacities, foaming capacity and stability, emulsion capacity and stability were evaluated. In this research protein extraction variables were pH (2.5-9.5), extraction time (20-80 min) and ratio (5-30). Results showed that; Isolates obtained by acid method had higher emulsification, and foam properties while alkalin method enhanced water absorption capacities and fat binding capacities. Whereas suitable functional properties of chick pea protein isolate could be used for substituting other proteins in food systems. Protein content of optimized Lathyrus sativus protein isolate (LPI) was 93.5% at pH 9.57, extraction time of 48.38 minute and 9.91 rations. L* value in LPI was less than CPI. Moreover, CPI significantly had higher protein solubility, foaming capacity, foam stability and emulsion stability and lower water binding capacity in comparison with LPI (p<0.05). pH changes had significant effect on protein solubility, foaming capacity, foaming stability, emulsion capacity and stability of both protein isolates (p<0.05). Furthermore, the lowest protein solubility, foaming capacity and emulsion capacity of both protein isolates were observed at pI. Study of DSC thermograph showed two peaks with high denaturation temperatures for both LPI and CPI, which confirmed the presence of high amounts of protein content with different protein fractions. Higher Td in LPI compared with CPI may be due to its higher amount of hydrophobic amino acids. Extrusion of legume flour except soybean is a new subject in the field of food processing. Considering that legumes are poor of sulfur amino acids (methionine, cysteine and tryptophan) and rich of amino acid lysine (protein grains limiting factor) legumes and cereals are taken into account as supplementary parts for each other from nutritional point view. chickpea and lathyrus sativusrice seeds contain some anti-nutritional factors such as phytic acid. Sprouting process can be used as one of the cheapest and most effective methods to improve the nutritional value. Therefore, in this study sprouted seeds were used in puffed corn snacks in order to enrich the production function. In the second phase of this work, A formulation containing germinated chickpea and germinated lathyrus sativus flour was extruded at a feed rate of 10 kg/h using a co-rotating twin-screw extruder. Primary extrusion variables were screw speed (100-200 rpm), feed moisture (14-20g/100gdb) and germinated flour concentration (10-40%). Response surface methodology (RSM) was used to study the effects of extrusion conditions on physical properties (density, hardness and expansion), functional properties (water absorption, oil absorption and solubility in water) and colorimetric parameters (L, a and b) of the extrudates. The experiment sample was a rotatable central square. Moreover, the optimized condition was calculated by a numerical optimization technique. The results of the optimization process, in order to maximize performance and improve physical properties and color characteristics, was concluded to be temperature 135.91oC, humidity 13% and screw speed 170.07 rpm and to be temperature 179.84oC, humidity 13.5% and screw speed 153.23 rpm for extruded snack based on germinated chickpea and germinated lathyrus sativus flour respectively.