The effect of longitudinal magnetic fields up to 60 kOe on the electrical resistivity of chromium‐iron alloys containing 0.9, 2.3, 3.3, 4.9, 9.5, and 11.2 at. % iron, have been studied at 4.2°K. All these alloys, except that with 0.9 at. % iron, exhibit negative total magnetoresistivity. The role of temperatures on the transverse magnetoresistivity at 12 kOe has been explored using the chromium‐9.5‐at. %‐iron alloy. The change in the magnetic component of the total magnetoresistivity has been calculated from the experimental data. This quantity is discussed from the viewpoint of a localized‐magnetic‐moment model.