Abstract: Contact stress of a disk blade coupled component is analyzed by numerical method.The contact problem is reduced to a problem of quadratic programming with linear inequality constraints(LCQP).Objective function of the LCQP is derived from the principle of minimum potential energy of elastic bodies in combination with finite element method.In order to formulate the constrain equations,an imaginary media is introduced between the two contact surfaces.Then the displacement compatibility condition on the contact region can be considered as to make the imaginary media have non negative volume during deformation.Such geometric condition will be presribed by a set of linear inequalities after discretization.Besides,static condensation technique is also used to reduce the degree of freedoms of the LCQP problem.A practical problem is estimated by our method and SAP5 software.These two results are in good agreement.