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Fresh beef is more expensive than frozen-thawed beef for its good quality and taste. Some unscrupulous traders labeled frozen-thawed beef as fresh beef for sale. The feasibility of using ultrasonic imaging technology to analyze and identify fresh and frozen-thawed beef was studied. Firstly, the texture, microstructure and some physical and chemical indexes of the fresh and frozen-thawed beef were collected to analyze their differences. Secondly, a total of 60 ultrasound images of fresh and frozenthawed beef were collected by ultrasound imaging system. Twenty common texture characteristic values defined by grey level cooccurrence matrix were collected. Then, principal component analysis (PCA) for data dimension reduction was used, and linear discriminant analysis (LDA) and support vector machine (SVM) were used to discriminate the samples. The result showed that there were significant differences (P＜0.01) in texture index, L* and cooking loss between fresh and frozenthawed beef. These differences combined with microstructural images showed that the tissue structure of frozen-thawed beef was damaged and the internal texture of frozen-thawed beef was poor. The ultrasound images of fresh and frozen-thawed beef showed significant differences, which could be well explained by the above studies. The texture features of the ultrasound image of fresh and frozenthawed beef were significantly different (P＜0.01).Both LDA and SVM had good discriminant results, especially LDA. When principal component signals were five, the precision rates of train set and test set of LDA were both 100%. The results showed that it was feasible to distinguish the fresh and frozen-thawed beef by using ultrasound imaging technology.