Exchange couplings in Sr2CrNO6 (N = Os, Ir) Double Perovskites (DPs) have been calculated numerically by using a Monte Carlo Simulation (MCS) in the frame work of Ising model by means of a relation between internal energy per site and magnetization per site. Two model parameters alpha and alpha' have been proposed for Sr2CrOsO6 and Sr2CrIrO6, respectively. The exchange couplings have been computed by varying alpha and alpha' through a MCS to find their values corresponding to the transition temperature 725K specific to Sr2CrOsO6 and 884K specific to Sr2CrIrO6. The exchange couplings J(Cr-Os) = -35:201meV, J(Cr-Cr) = 5:452 meV and J(Os-Os) = 14:873 meV have been obtained for Sr2CrOsO6, while J(Cr-Ir) = -24:464 meV, J(Cr-Cr) = 2:181 meV and J(Ir-Ir) = 16:730 meV have been obtained for Sr2CrIrO6. Magnetization and magnetic susceptibility have been investigated in both compounds. Internal energy per site has been given. (C) 2017 Elsevier B. V. All rights reserved.