Compared with radical and external radiotherapy for prostate cancer, particle implantation has a low incidence of various complications and better management of complications. Complications of particle implantation therapy include short-term complications and long-term complications. Complications occurring within one year are usually defined as short-term complications, while those occurring after one year are defined as long-term complications. These complications mainly involve the urinary tract, rectum and sexual function. 1. Brachytherapy is less invasive and easier for patients to accept. Compared with radical prostate cancer surgery, brachytherapy is less traumatic and has a lower incidence of phimosis and urinary incontinence, but its urinary tract irritation symptoms are more pronounced than those of radical prostate cancer surgery. Common urinary tract irritation symptoms in the early postoperative period include urinary frequency, urgency, painful urination, weakness, incomplete urination and increased nocturia, which are common in the first month after surgery. However, most patients will gradually return to normal levels within 6 to 12 months. Combined external radiotherapy can aggravate lower urinary tract symptoms, and the incidence of acute urinary retention has been reported in the literature to be around 5%, associated with high preoperative IPSS scores, large prostate volume (>35 ml) and residual urine volume >200 ml. The use of long-term alpha-blockers can reduce the symptoms of postoperative voiding obstruction and decrease the incidence of urinary retention. The incidence of postoperative urinary incontinence is low, 0-11%, and is higher in patients with a history of TURP surgery. 2. One of the main advantages of particle therapy is the protection of sexual function. Most reports suggest that the retention rate of postoperative erectile function can be more than 80%. The cause of postoperative erectile dysfunction is still unclear, and some authors suggest that it may be related to radiation damage to the vascular nerve bundle, and some articles point out that the radiation dose received by the urethral bulb has a strong correlation with postoperative erectile dysfunction. The retention rate of erectile function is related to the preoperative erectile function status, the radiation dose received by the prostate, and the presence of endocrine therapy or external radiation therapy. eric et al. reported that after 181 patients with good preoperative sexual function were treated and followed up for 6 years, the retention rate of sexual function was 39% for those treated with brachytherapy + external radiation therapy and 52% for those without external radiation therapy, and as the follow-up time increased, the retention rate of erectile Stock et al. reported that the retention rate was 79% at 3 years and 59% at 6 years after surgery. 3. Proctitis is also a common complication of brachytherapy, with an incidence of 1% to 21,4%. Mostly manifested as rectal irritation symptoms such as increased number of stools, urgency, excessive rectal mucus or intermittent mild blood in the stool, often self-limiting, generally symptomatic treatment can be. In severe cases, rectal ulcers or even urorectal fistulas can occur, but they are very rare.