At the present stage of development of the Russian economy the special attention is paid to attraction of investments into agrarian and industrial complex. The new investment policy in the agricultural sector should provide a breakthrough in improving the efficiency of production. The question of influence of an investment and tax policy on competitiveness of agro-industrial complex is considered. The special attention is paid to the principles of the regional investment policy stimulating investment activity of subjects of the market. Need of improvement of a tax policy for increase of competitiveness of agrarian production in the Republic of Mari El is defined. The package of measures on improve-ment of an innovative and tax policy in agricultural production is offered. Realization of the above-stated measures will promote increase of competitiveness of agro-industrial complex of the Republic of Mari El and the solution of questions of import substitution in the food market of Russia.