One- and two-step procedure syntheses of epoxyfumarate resins are presented. In the two-step procedure, acidic ester of maleic acid was synthesized separately and then used for the addition reaction with epoxy resin, Epidian 5. In the one-step procedure, synthesis acidic ester was formed during the synthesis process. Properties of the resins obtained in the one-and two-step procedures, in a noncrosslinked state during curing and after crosslinking, were compared.