A comparative analysis has been made of the influence of highly popular synthetic and natural depressing additives on the low-temperature properties of commercial summer diesel oil and its blends with catalytically cracked light gasoil, and also those of the straight-run heavy diesel fraction. The optimal depressing-additive concentration and component composition of the blend of summer diesel oil and catalytically cracked light gasoil at which the pour point of the summer diesel oil can be lowered to the maximum are established.