In order to monitor the biological tissue lesion when using HIFU to treat, a method that biological tissue lesion identification based on ultrasound image by Graylevelgradient cooccurrence matrix and FCM clustering is proposed. First, obtaining ultrasound images of fresh pork tissue which irradiated by high intensity focused ultrasound and extract parameters of Gray levelgradient cooccurrence matrix after preprocessing. The parameters of gray entropy and entropy of mixing are the characterization parameter of identification of biological tissue lesion. And then using FCM clustering method to analysis. The results show that the rate of identification is higher when combining Gray entropy with entropy of mixing to identify biological tissue lesion than signal parameter, which is 332 percentage more than that gray average and wavelet transform coefficient method. Thus,this method can better identify tissue lesion in the course of HIFU treatment. The method is helpful to improve the efficacy of HIFU treatment, relating the noninvasive temperature measurement with tissue lesion identification further.