Arterial blood pressure was measured noninvasively using Doppler ultrasound and an occluding cuff. The subjects were 28 domestic pigs (10-49 kg) anesthetized with pentobarbital sodium (25 mg/kg). Indirect pressure measurements were made with the Doppler unit placed over the radial or the ulnar artery proximal to the carpal joint. Comparison was made with directly measured pressure to determine the reliability and reproducibility of the indirect method. Direct systolic pressures between 73 and 230 mmHg and diastolic pressures between 52 and 165 mmHg were measured. There was no significant difference between directly and indirectly measured systolic pressure (P greater than 0.20). Indirectly measured diastolic pressure tended to be lower than direct diastolic pressure, the difference by the paired t test being significant to P = 0.06. For systolic pressure the sample correlation coefficient was 0.94, and for diastolic pressure, 0.88. Both systolic and diastolic blood pressure can be accurately measured in the anesthetized pig using Doppler ultrasound and an occluding cuff.