Abstract: Objective: To explore the diagnostic value of contrast-enhanced ultrasound based on MRI/US cognitive fusion in prostate cancer. Methods: A total of 83 patients with suspected prostate cancer were selected due to prostate specific antigen (PSA) elevation(≥4 ng/mL) or abnormal digital rectal examination.All patients were detected by the MRI,fusion contrast-enhanced ultrasound and perineal prostatic system puncture.For patients with positive findings in MRI or fusion contrast-enhanced ultrasound images,the fusion contrast ultrasound-guided transperineal prostate targeted puncture was added.Using the puncture histopathology as the gold standard,the diagnostic efficacy of fusion contrast-enhanced ultrasound in prostate cancer was analyzed and compared with that of MRI. Results: Among the 83 patients,37 cases were diagnosed as the prostate cancer(malignant group) and 46 cases were diagnosed as the benign lesions(benign group).There was no statistcial significance in the age between the benign group and malignant group(P>0.05),but the differences of the PSA,free PSA,PSA density and PI-RADS scores were statistically significant between the benign group and malignant group(P<0.05 to P<0.01).There were 24 cases of prostate cancer and 39 cases of benign lesions by the diagnosis of fusion contrast ultrasound,with sensitivity of 64.86%(24/37),specificity of 84.78%(39/46) and accuracy of 75.90%(63/83).Twenty cases of prostate cancer and 43 cases of benign lesions were diagnosed by MRI,the sensitivity was 54.05%(20/37),the specificity was 93.48%(43/46),and the accuracy was 75.90%(63/83).The differences of the identification of prostate cancer at different locations were statistically significant between fusion contrast ultrasound and MRI(P<0.01).Compared with MRI,the fusion contrast ultrasound showed higher sensitivity and accuracy in the diagnosis of prostate cancer(P<0.01),but there was no statistical significance in specificity between the two(P>0.05).The results of ROC curve analysis showed that the AUC of fusion contrast ultrasound for diagnosis of prostate cancer was 0.75,which was higher than that of MRI(0.74). Conclusions: The fusion contrast-enhanced ultrasound can improve the detection rate of prostate cancer,and further reduce the missed diagnosis of prostate cancer.