Solar panel can act as a medium for transforming sunlight into electrical energy. Nevertheless, not all of the sunlight received on this device can be converted into electrical energy and the remainder will be dissipated into thermal energy. If a solar panel is continuously exposed to the sun, so its temperature will increase and thereby reduce its electrical efficiency. To deal with the issue, it may combine a PV panel with a thermal collector which is called a hybrid PV/T collector. Furthermore, in the present study the effects of fluid flow direction and mass flow rate on the thermal and electrical efficiency of the PV/T collectors are extensively analyzed. Single and double pass collectors with rectangular plate fin absorber were attached to backside of the PV panel. They were tested using a solar simulator with different flow rate ranging between 0.01 and 0.05 kg/s of the working fluid. The results show that the use of double pass PV/T air collector increase its performance compared with the single pass one. The highest values obtained from this type collector are found to be 73.23% in the thermal efficiency and 10.16% in the electrical efficiency with the working fluid mass flow rate of 0.048 kg/s.