The influence of relevant geometric parameters on the flow characteristics and aerodynamic characteristics of the plasma jet airfoil is studied by wind tunnel experiments and numerical simulation methods, and the flow control mechanism is described. Slots at different heights are designed, and flow rate and jet velocity at the outlet of the slot under plasma excitation are studied. The slot of 4 mm being selected as an optimal parameter,and a plasma co-flow jet airfoil is designed by taking NACA0025 as a referenced airfoil. The lift or drag characteristics of the plasma co-flow jet airfoil are studied by numerical simulation. The results show that Re being equal to 68 000,  Up-p being equal to 13 kV, and f being equal to 8 kHz, the stall angle of attack increases from 8°to 14°, and the maximum lift coefficient is increased by 181% compared with the reference airfoil. The drag of the plasma jet airfoil decreases continuously with the increase of the angle of attack. Prior to an angle of attack of 10o, the drag is greater than the reference airfoil, and then smaller than the reference airfoil. The lift-drag ratio result shows the same variation characteristics as the drag and is better than the reference airfoil beyond the angle of attack of 10o because the trailing edge slot generates a positive drag at a small angle of attack, and the local drag becomes negative as the angle of attack increases. In contrast to the only leading edge blowing, the co-flow jet can increase the stall angle of attack from 12° to 16° because the co-flow jet airfoil can inject momentum locally through the blowing effect on the leading edge, and the suction effect on the trailing edge can reduce the low energy separation area to increase circulation.