Two current configuration models of deep level native defect EL2 in GaAs, i.e. pair model As_(Ga)-As_i of Bourgoin and ternary complex As_(Ga)V_(As)V_(Ga) of Zou Yuanxi are in- troduced. The densities of vibrational state for these two models are calculated. The differ- ence between two kinds of density of state will provide useful information for final identifi- cation of the configuration of EL2.