The paper presents an theoretical model for the kinetics of lipid peroxidation (LP), which takes into account the synergy effect of vitamins C and E for 5 reagents: InH, In •, R •, ROO • and ROOH: dRdt = wi + kR1SR1 – kRYR – kiI1R , (1) dR1dt = kRYR – kR1SR1– ki1I1R1 – k2r1R12 , (2) dP1dt = kR1SR1 + ki1I1R1 – (kd1+ kd2)P1 , (3) dI1dt = kaI2A – kiI1R – ki1I1R1 , (4) dI2dt = kiI1R + ki1I1R1 – kaI2A , (5) here the following designations are introduced: S = [RH], Y = [O2], R = [R •], R1 = [ROO •], P1 = [ROOH], I1 = [InH], I2= [In •], A = [AscH–]. And also kd1 and kd2 are the rate constants of lipid hydroperoxide decomposition, ki and ki1 are the rate constants of inactivation of R • and ROO • radicals, kR1 are the rate constants of radical oxidation of the RH substrate by the ROO • radical, k2r1 is the rate constant of quadratic recombination of the ROO • radical. In this model, it is believed that the lipid substrate RH, oxygen O2, and ascorbic acid AscH– are present in excess; in a first approximation, their concentrations can be considered constant: S≈S0, Y≈Y0, A≈A00 For different types of cell membranes and different physicochemical conditions for the initiation and course of the peroxidation process, this model, when using an appropriate set of model parameter values (reaction rate constants and initiation rate), makes it possible to determine the concentrations of conjugated antioxidants that are optimal for effective control.