Abstract: The differences of moisture distribution and water retention of Tan sheep meat under still air with 25,10 ℃and 5 ℃ were studied by using low field nuclear magnetic resonance equipment. By comparing with chilled Tan sheep meat,the relaxation time of the water which was hardly to flow decreased obviously in the Tan sheep meat by freeze- thaw process,and the relative amount increased evidently,while the relaxation time of free water had been distinctly increased,and the relative amount decreased evidently.By comparing the Tan sheep meat thawed under different temperatures,the relaxation time of free water in Tan sheep meat had significant increased as the thaw temperature went down. Considering the change of hydraulic and pressurized water loss rate,relevant analysis concluded the water retention of Tan sheep meat increased as the thawing temperature decreased within a certain range.The experimental results showed that the magnetic resonance imaging could quickly characterize the moisture content of Tan sheep meat.