This article proposes the concept of development of the method for teaching Italian as a second foreign language based on the three most common foreign European languages - Spanish, English and French. Basing on the experience of teaching Italian as a second foreign language, the main problems encountered in the course of study and preventing the achievement of the minimum required level of preparation in the second studied language were identified. Primarily, there is significant heterogeneity of the students in groups both concerning the level of training in the first foreign language and the factor of dissimilarity of the various primary foreign languages. It affects the extent of comprehensibility of the material by the students, which varies considerably within the framework of lessons in the main sections of the language. The basic idea of the proposed methodology is to determine the optimal composition of the groups, as well as the scope and contents of the segments of the training programs and methodical plans of the lessons, aimed at practical studying of the main sections of the language - phonetics, grammar, morphology and syntax. The solution of this problem is proposed to be carried out by mathematical, statistical research methods: to optimise the composition of training groups it is logical to apply the technique of cluster analysis and to use the regression analysis method to compile the most effective curriculum. The rationale for the methodology proposed by the above-mentioned methods is to be carried out on a representative sample of at least fifty students of Italian as a second foreign language - the second, the third and the fourth year students of the bachelor's degree and two years of the master's program of the Institute of Foreign Languages of the of Peoples' Friendship University of Russia. The results of the study can be implied in linguistic departments of higher educational institutions in order to stimulate progress in study of the Italian language.