The authors assess the contemporary legislation of complex exam (integration test) of foreign nationals, basing on the analysis of the general aims of legal declaring of a Russian language as a national language of the Russian Federation, namely solidarization of the nation and providing the common communication space in the society. The inquiry of the Russian legislation and practice of its enforcement shows a number of defects in the regulation of complex exam foreign nationals in Russian as a foreign language. The authors suggest legal measures to rectify these defects following the aims of proclaiming a language to be the national language.