Splenic blood flow and splenic volume were measured by Doppler and cross sectional ultrasound in 72 human subjects consisting of 61 patients with splenomegaly and 11 normal subjects. This non-invasive and relatively simple method yielded satisfactory results in 76% of the subjects studied; failures were due to obesity, debility, distorted vascular anatomy, and excessive gas in the stomach. These preliminary results suggest that the Doppler ultrasound technique is a practical clinical method for measuring splenic blood flow.