FIELD: chemical industry. SUBSTANCE: described are stabilized composition comprising, calculated for total weight, (a) from 25 to 89 wt % of organic phosphite or phosphonite, (b) from 0.01 to wt % of organic amine and (c) from 0.01 to 25 wt % of acid binding metal salt, and also method of stabilization of organic phosphites or phosphonites against hydrolysis by addition of organic amine and acid binding metal salt. Said compositions have outstanding stability when stored under conditions of higher air humidity. Claimed composition and product stabilized by claimed method are useful as stabilizers of organic materials against destructive effect of heat, oxygen and/or light. EFFECT: improved properties of the stabilized composition. 12 cl, 4 ex, 4 tbl
