The use of magnetic resonance (MR) imaging in two cases of rhabdomyolysis, one resulting from prolonged muscle compression and one from electrical burns, is described. The involved muscles were clearly demonstrated with MR. Recognition and assessment of the extent of rhabdomyolysis are important since life-threatening sequelae including severe metabolic disorders are possible. In one case, spin-echo and inversion-recovery MR imaging provided greater detail of muscle abnormalities than did 99mTc-pyrophosphate radionuclide scanning. Both cases illustrate the usefulness of MR in evaluation of skeletal muscle disorders.