Object To analyze the application value of Superb microvascular imaging (SMI) semi-quantitative classification in the detection of prostate cancer. Materials and methods Screened 129 patients with prostate disease diagnosed pathologically, and took biopsy histopathology as the diagnostic gold standard. Benign diseases such as prostatic hyperplasia and prostatitis were included in the benign group, a total of 40 cases; prostate acinar adenocarcinoma was included in the malignant group, a total of 89 example. Suspicious lesions detected by gray-scale ultrasound and SMI are used as evaluation target areas of the SMI semi-quantitative analysis. Refer to Adler blood flow grading and synovial semi-quantitative scoring system of the evaluation the proportion of blood flow to semi-quantitatively classify the prevalence of fine blood within the lesion. Grade 0: No fine blood flow in the lesion; Grade I: Probe 1 -2 sparse punctate blood flow signal within the lesion ; Level II: 3-4 short-line blood flows within the lesion, and the distribution does not exceed 50% of the maximum cross-section of the lesion; Level III: Detection within the lesion and more than 4 blood flows and distribution It accounts for more than 50% of the cross-section of the lesion. Results In the benign group, there were 7 cases of SMI grade 0, 9 cases of grade 1, 12 cases of grade 2, and 12 cases of grade 3. In the malignant group, there were 2 cases of SMI grade 1, 10 cases of SMI grade 2 and 77 cases of SMI grade 3. The performance of SMI in the benign group was different, while in the malignant group, there were 77 cases of SMI grade 3, accounting for 86.5%. The diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy of SMI for prostate cancer were 86.51%, 70.00%, 86.51%, 70.00%, and 81.39%, respectively.Conclusion Based on the combination of two-dimensional ultrasound, SMI semi-quantitative classification has certain application value in the identification of benign and malignant prostate tumors. It can be combined with blood PSA for early screening of prostate cancer.