The experiments of pressure shift freezing (PSF) and conventional freezing were conducted on beef, and the thermal behaviors and ice crystal properties in freezing process were analyzed. The PSF experiments at 100MPa (-9℃), 150MPa (-15℃) and 200MPa (-20℃) were performed as well as conventional air freezing (CAF) and liquid immersion freezing (LIF) at -20℃ and 0.1MPa. The results show that most of the ice crystals formed in conventional freezing is extracellular, the size is large and non uniform, and severe strain and mechanical injuries has happened on the tissue cells. The crystals formed in PSF have smaller and more uniform size and spread more evenly in samples than that in conventional freezing. And the higher the pressure was, the more crystals formed in intracellular spaces and the less cell injuries happened. The freezing time in CAF is 85min, in LIF is 5.5min, and is 2.47, 1.22 and 0.83min when subjecting to 100, 150 and 200MPa PSF treatments; the degree of supercooling formed in depressurization increases with pressure increasing. However, the freezing point drops with and the freezing time needed reduces with the pressure increasing.