Abstract: The low-field nuclear magnetic resonance (LF-NMR) technology was used to detect the transverse relaxation time of water in frying process. The water distribution in the steak was compared according to the difference of the transverse relaxation time T₂, and the change of the water holding capacity was determined by the pressure loss rate and the cooking loss rate index during the decoction of the treated steak. The results showed that there were significant differences in pressure loss rate and cooking loss rate between the six groups (p<0.05).With the increase of the frying temperature and the time, the pressure loss rate and the cooking loss rate were increasing, the transverse relaxation time (T₂) of the three kinds of water was moving to the slow relaxation direction. As the water degree of freedom and the flow rate increasing, the combination degree was decreasing continuously, which showed that the water's ability to be reduced by the steak system. The shift of relaxation time of water in the T₂₂ state was more significant with the increasing maturity of the conditioning steak.