The nonequilibrium theo1y of strongly conelated systems is proposed. This theo1y is grounded on the generalized Wick theorem. This theorem is employed for calculation of the the1mal averages of contour a1rnnged products of electron operators by generalizing Keldysh fo1malism. Perturbation expansion is realized for Anderson impurity model in which we consider the Coulomb interaction of the impurity electrons as a main parameter of the model and the mixing interaction between impurity and conduction electrons as a perturbation. The first two approximations are used and has obtained the value of the cmTent between one of the leads and central region of interacting electrons. The contribution of the strong conelations and of ineducible diagrams is analyzed. For the system in nonequilibrium we employ the Keldysh [1] fo1malism based on the contour of the time evolution and the systems of four Green's functions for the both subsystem of localized and free electrons with operator d a, d; and C'ka , c;a conespondingly. We use the time-ordering and anti-time ordering of the Heisenberg operators. For leads conduction electrons we use the localized mode and investigate the influence of the localized electrons of this collective mode bJ.a = LJii/4Ck/4a on conduction electrons. The system of four Green's function of localized electrons has, in the notification of [2], the f01m where T and f denote the time and anti-time ordering. The analogous definitions exist for the Green's function of he lead's electrons marked in as q· and so on. In Keldysh fonnalism we use the matrix Green's functions composed from different elements of the evolution in contour space. We have the matrices We fo1mulated the nonequilibrium pe1turbation theo1y supposing that the time evolution is realized along the real-time contour, which struts and ends at t = -<XJ. The the1mal average at t = 0 can be obtained in the fo1m Operators with tilde Hi are in interaction representation. The expansion of the exponents is the realization of the pe1turbative theo1y.