Abstract: In this study,sunflower seed of removing phenol was used as raw material,and the effects of sunflower seed crushed particle size and various aqueous enzymatic extraction conditions on the extraction rate of sunflower seed oil were studied. The process of sunflower seed crushing and each phase were studied by CLSM. And the internal mechanism of optimum technical condition was clear. The partical size of sunflower seed by fine pulverize was 19.68 μm,significantly improved the free oil yeild. Optimum conditions for aqueous enzymatic extraction were as follows:Alkali protease Probex 6L for 2 h,1:5 (w/v),2 h,1.5%(v/w). Under the optimum conditions the free oil yield was 92.48%. CLSM further demonstrates that the finely comminuted sunflower seed material was smaller and more uniform than the shear comminuted sunflower seed. Compared with the commercially available low-temperature pressed sunflower oil,the sunflower oil extracted by aqueous enzymatic method reaches the standard of cold-pressed first-grade oil in the main physical and chemical indicators,and its trans-fatty acid was significantly lower than that of commercially available sunflower oil. The oil extracted by the aqueous enzymatic method has better quality,higher oil yield and obvious advantages.