The invention relates to a finite element method based aircraft cabin door seal load computing method. The sealing strip stress condition is simplified to be a plane strain state; modeling, loading and definition contact are performed on a sealing strip, a support and a cabin door, so as to resolve the stress for compression of the sealing strip per unit length, and the sealing strip is between the support and the cabin door; a revolute pair is defined at a hinge of the cabin door and rotation angular displacement is restrained, and pressure equivalent to the sealing compression force of per unit length is applied on the cabin door at the sealing position, so as to obtain bending moment of the hinge, namely, the cabin door seal load. The method solves the problem of moment computation caused by sealing in automatic closing and opening of the aircraft cabin door, provides design basis for design of an automatic closing and opening mechanism of the cabin door, and is initiative at home.