The orthogonality relations of multivariate Krawtchouk polynomials are
discussed. In case of two variables, the necessary and sufficient conditions of
orthogonality is given by Gr\"unbaum and Rahman in [SIGMA 6 (2010), 090, 12
pages, arXiv:1007.4327]. In this study, a simple proof of the necessary and
sufficient condition of orthogonality is given for a general case