Whilst a normal inverter converts the DC voltage into AC voltage, an off grid inverter occupies input from either solar panel or wind turbine. This paper is about the design and simulation of a bi-input inverter using PV and Wind power system. The overall design will result in a regulated AC output load for AC grid connected system. This paper also discusses on two circuits which is charge controller and inverter. It is found that regulated output AC voltage level of 110 V and current 13 A have been successfully simulated using MULTISIM Power Pro Edition 12.0 which is applicable for national 50-Hz transmission grid line. © 2013 IEEE.