Abstarct: In this thesis, a controller for power injection of a photovoltaic (PV) microinverter to the grid is presented. Microinverter has two-stage topology that consists of a conventional DC/DC boost converter and a DC/AC inverter. Grid is modeled with a sinusoidal voltage source and is connected to the inverter output by an LCL filter. Thus, the system has a relatively high order that makes its control system design challenging. Microinverter control system consists of two loops that the external loop is maximum power point tracking (MPPT) and internal loop is power control. MPPT algorithm determines reference current where maximum power is occurred. MPPT iplementation is done using DC/DC boost converter that regulates DC voltage simultaneously. We implement MPPT and output voltage regulation of the converter via finite control set model predictive control (FCS-MPC). Due to that the outer loop time constant is much large compared to the inner loop, they can be considered decoupled. Our main goal is to inject a desired pure active power into the grid. This is done by controlling the output current. To achieve this goal, a FCS-MPC is proposed that controls the injected power by controlling output current and also ensures boundedness of other state variables. Unlike the classic controllers, the proposed controller is quite simple and does not require any other control loop or modulator for practical implementation. Simulation results show the effective performance of proposed control scheme under various conditions.