The magnetization curves of YBCO crystal prepared by melt-textured growth method were measured from 1.5K to 89K. Flux jumps were observed for H‖ c at 1.5K, 7K and 10K. Peak effects were observed for H‖ c in the temperature range of 15-83K. The anisotropies of magnetization curves and magnetic critical current are analysed in detail. The properties of connection between grains and the pinning mechanism are discussed.