The constitutive androstane receptor (CAR) is a nuclear receptor that participates in the regulation of biotransformation of toxic substances and metabolic processes. The mechanisms of expression changes of CAR under conditions of oxidative stress (OS) have not been studied yet and this was the purpose of the study. OS was modeled by incubating Caco2 cells with hydrogen peroxide 10-100 μM for 72 h. The amount of CAR was determined by the Western blot, nuclear factor erythroid 2-related factor 2 (Nrf2) was evaluated by a heterogeneous enzyme immunoassay malondialdehyde (MDA), the lipid peroxidation products (LPP) was assayed by a photometric method. Incubation of cells with 10 μM and 50 μM H2O2 led to an increase in the amount of CAR and Nrf2, while incubation with 100 μM H2O2 caused their decrease. Nrf2 inhibition did not influence the CAR content under OS conditions. 10 μM MDA increased the CAR content, 100 μM MDA had no effect, while 150 μM reduced the amount of CAR.