This paper describes the method for detection of the misfired cylinder by analysis of the variation of pressure occurred in exhaust manifold on an MPI gasoline engine. Misfired cylinder(s) cause a loss of power, an increase of fuel consumption and exhaust emission and vibration is caused by unsteady torque. Therefore early detection and correction of misfired cylinder(s) play a very important role in the proper performance and the exhaust emission. The method is a comparison of integration pressure index during the period of a blowdown in the displacement period. Experimental results showed that the method, using the variation of pressure in the exhaust manifold is proven to be effective in the detection of single cylinder or multiple cylinders misfire on the gasoline engine regardless of the engine revolutions. In addition, this method, using the variation of pressure in the exhaust manifold is a very easy and accurate method compared with other methods.