We extend the traditional RBF network to be a more powerful tool in terms of considering dependence among explanatory variables. For this purpose, we propose two kernel functions of RBF network, i.e., FGM-Gauss kernel and ρ-Gauss kernel based on a copula. A copula is another expression of a joint probability distribution function. After proposing the new models, we compare the regression performances between RBF network with the traditional Gauss kernel, FGM-Gauss kernel, ρ-Gauss kernel, and the multiple linear regression analysis by numerical experimentations. We show that new models have better regression performances than RBF network with Gauss kernel and multiple regression analysis if the explanatory variables depend on each other.