In this paper we propose an analytical model to investigate the influence of the depth and thickness of the composite photoactive layer, on the optical and electrical properties of the hybrid solar cell based on the mesostructured perovskite CH 3 NH 3 PbI 3 . Using Bruggeman theory, energy conservation equation and charge density continuity equation, allowed us to determine the optical generation rate and the short-circuit current density. The results obtained show that the optical generation rate decreases according to the depth. We also see that this optical generation rate increases with the thickness of the photoactive layer. For the short-circuit current density, we note that it increases with the thickness and there is an optimum thickness at 850 nm. Our results agree with those found in literature.