Post-prostate cancer psa, or prostate-specific antigen, is ideally low to undetectable. Prostate-specific antigen is basically produced by all prostate tissues or prostate cancer cells, while surgery will generally remove all prostate tissues and cancerous tissues, theoretically, there will be no prostate-specific antigen production, so the optimal state is low to undetectable after surgery. However, in order to facilitate clinical evaluation and clinical research data collection, it is routinely set that the value of prostate-specific antigen after prostate cancer surgery is less than 0.1ng/ml as normal, if the detection is greater than or equal to 0.1ng/ml, then it is considered that there are residual tumor or prostate tissues or metastasis before surgery, and further examination and treatment is needed. It takes time for prostate-specific antigen to decline after prostate cancer surgery, and the test is usually conducted 4~8 weeks after surgery to evaluate the effect of surgery. After prostate cancer surgery, please follow the doctor’s instructions for timely review, evaluation of the condition by a specialist physician, and treatment in accordance with the physician’s advice.