The temperature dependence of coercive force Hc(T) of pressed powders of ferromagnetic half metal CrO2 is compared to the temperature dependence of the maximum field of positive tunneling magnetoresistance Hp(T). It is established that the multidomain alters the nature of the reverse magnetization of
transport channels and violates relation Hp ≈ Hc at low temperatures (4.2–70 K).