The present invention provides a method for determining influence of a boundary layer absorption effect on lateral aerodynamic characteristics of a distributed propulsion aircraft, and belongs to the field of distributed propulsion airplane aerodynamic characteristics analysis. The method comprises: first establishing a boundary layer absorption effect oriented three-dimensional comprehensive calculation model, and setting control parameters of engines that are arranged on a left wing and a right wing to be independently adjustable; setting the control parameters of the engines arranged on the left and right sides of wings, and separately calculating and obtaining flow inlet parameters and speed outlet parameters of the engines on two sides, and corresponding boundary layer absorption degrees of the left and right sides; and performing flow field simulation and calculation, so as to obtain lateral aerodynamic characteristics of an airplane when a difference exists between boundary layer absorption effects of the two sides. According to the method provided by the present invention, a difference between boundary layer absorption degrees of the left and right sides can be precisely simulated, and calculation of data of lateral aerodynamic characteristics of the airplane is high in accuracy, and the obtained airplane lateral aerodynamic parameters are relatively high in reliability.