Abstract
We study the b s decay including the next-to-leading QCD corrections in the two Higgs doublet model with flavour changing neutral currents at the tree level. We find the constraints to the flavour changing parameters of the model, using the experimental results on the branching ratio of B Xs decay, provided by the CLEO Collaboration. The restrictions coming from the F = 2 (F = K, D, B) mixing and the parameter.