Eleven magnetic resonance(MR) and CT imagings were performed in nine patients with mild to moderate degree oddelayed neuropsychiatric symptoms following acute carbon monoxide(CO) poisoning, to evaluate the capability of MRin demonstrating any additional finding to CT. The MR images were obtained using 0.15 Tesla resistive system withvariuos combination of three pulse sequences, including partial saturation recovery, T2-weighted spine echo andinversion recovery. Bilateral white matter abnormalities suggesting demyelination were demonstrated in 4 patientswith MR and in only 2 patients wtih CT. The contrast discrimination between normal and abnormal white matterproved to be better with T2-wieghted spin echo and inversion recovery than with partial saturation recovery andCT. But necrosis of the globus pallidus(1 patient) and diffuse atrophy(3 patients) were equally demonstrated onboth MR and CT. It is suggested that MR be used as a initial imaging method in the evaluation of the delayedencephalopathy following acute CO poisoning, especially for the detection of the possible white matter lesions.