In present work the effective singlet-triplet model for CuO2-layer on the grounds of multiband p-d model of strongly correlated electrons is obtained. The resulting Hamiltonian has a form of generalized singlet-triplet t-t-J model for p-type superconductors and form of usual t-t-J model for n-type superconductors. In the mean field approximation in X-operator representation we derived equations for Gorkov type Green functions. The symmetry classification of the superconducting order parameter in case of tetragonal lattice resulted in d_{x^2-y^2}- and d_{xy}-types of singlet pairing for both p- and n-type superconductors while s-type singlet pairing dont take place. Also normal paramagnetic phase of effective singlet-triplet model was investigated and dispersion over Brillouin zone, density of states and evolution of Fermi level with doping were obtained.
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