Money stock variation is one of the main results of monetary policy performance of the banks. Therefore the banks are the most important economic institutions that have basic role in operating economic policies. The aim of this paper is to test for exogeneity hypothesis of consumer price Index differences in respect to banks deposits indexes and, also to estimate inflation elasticity coefficient in respect to banks deposits variations. The results show that inflation is endogenous in relation to different kinds of banks deposits. Also inflation elasticity of the total banks deposits estimated to be 0.48 to in the Iranian economy