A model has been developed to simulate the performance of MIS/IL silicon solar cells taking into consideration the effect of cell surface parameters, namely, positive fixed oxide density, surface states density and mobile charge density on the current components. We consider a MIS/IL device on p-type semiconductor substrate. A complete set of equations is used which include the diffusion current (J(diff)), the hole and the electron tunneling currents through the oxide layer (J(ht), J(et)), the surface states current components (J(hs), J(es) and J(ss)), the generation-recombination current in the transition region (J(RG)), and the photocurrent generated in the bulk in the transition region (J(LN)). The results show that the photogenerated current, surface state current and the tunneling current have the dominant effects on the cell performance.