Abstract. Let E be Galois extension of Q of finite degree and let π and π ′ be two irreducible automorphic unitary cuspidal representations of GLm(E A ) and GL m ′ (E A ), respectively. We prove an asymptotic formula for computation of coefficients γ π,π ′ (k) in the Laurent (Taylor) series expansion around s = 1 of the logarithmic derivative of the Rankin-Selberg L−function L(s, π × π ′ ) under assumption that at least one of representations π, π ′ is self-contragredient and show that coefficients γ π,π ′ (k) are related to weighted Selberg orthogonality. We also replace the assumption that at least one of representations π and π ′ is self-contragredient by a weaker one.