It is a phase II single-arm clinical trial. The primary endpoint is diagnostic sensitivity of the Ga-68 PSMA ligand in prostate cancer. The four outcomes (true positive, false positive, true negative, and false negative) can be defined based on the process as Figure 1 and formulated in a 2×2 contingency table, and the related sensitivity, specificity, and accuracy will be calculated based on the test results of enrolled subjects. All subjects enrolled must meet eligibility criteria based on the inclusion/exclusion criteria detailed in Section 5.4 and 5.5.