Nuclear magnetic resonance (NMR) imaging is a valuable diagnostic tool that detects the presence of hydrogen protons or water in material studied. Recently the technique was successfully used to observe the occurrence of defects within logs. The present study examined the feasibility of using NMR imaging for analyzing moisture distributions within white oak (QuercusalbaL.) lumber. At selected days during drying, three thicknesses of lumber were imaged to detect free water, using a clinical 0.5-T whole body NMR scanner. NMR was shown to provide a noninvasive image of the internal structure of lumber. Images revealed that growth ring orientation and rays may play an important role in the drying process. Moisture distributions (shell and core) were qualitatively observed. For a quantitative interpretation, images were measured with an optical densitometer. The average moisture content of the board was correlated successfully to the weighted average optical density for the shell and core regions combined.