A study has been made of the effect of additions of phosphorus, lanthanum and zinc on the activity of zeolite-containing catalyst SGK-1 modified with chromium in the conversion of a mixture of C-2-C-4 gases into liquid C-5-C-10 hydrocarbons (gasoline components). It has been established that the introduction of additives (P, La and Zn) increases the selectivity and yield of liquid hydrocarbons. The dependence of the composition of products of conversion of C-2-C-4 gases on the temperature and the time of operation of the catalysts has been studied.