Since plants confront to kinds of environment stresses in life cycle, exogenous glycine betaine (EGB) applications on crop plants that unable to synthesis glycine betaine is a possible approach to overcome the environmental limitations. In order to study of different treatments of EGB on physiological and morphological characteristics of soybean (Glycine max var PER and DPX), experiments were performed in field condition as factorial with completely randomized design in four replication. Treatments consist of 0 (as control), 2.5, 5, 7.5 and 10kg per hectar EGB in sixleaf and near the flowering stages. During the growth period the amount of chlorophyll and soluble sugar levels in leaves and proline, GB and total protein in leaves and seeds and morphological factors, including number of branches, pods, seed number in pods, thousands seed weight were measured. The results showed that chlorophyll content had no change by application of EGB. Regard to EGB, proline and soluble sugar content not observed significant different in ten foliare stage. All EGB concentrations increased number of lateral branch and number of seeds per pod significantly, but not abserved significant different in number of seed per pod and thousands seed weight. EGB application enhanced yield of soybean by increase in number of lateral branch and number of pod per plant. Increased EGB concentrations enhanced yield of soybean significantly, especially in DPX cultivar by optimum concentration of 7.5, 10 and 5 Kg/hec and 5. Total protein content, germination percent and rate in harvested seeds in different treatments of EGB have no significant different.