The incidence of prostate cancer is high in Europe and the United States. In recent years, the incidence of prostate cancer in China is also increasing year by year. With the advent of PSA testing and ultrasound-guided prostate puncture biopsy, many cases of prostate cancer can be diagnosed at an early stage. Treatment for “early stage prostate cancer”, also known as “limited prostate cancer”, includes radical prostatectomy, radical external radiation therapy, three-dimensional conformal radiation therapy, complete androgen blockade therapy, and prostate brachytherapy (Prostate Brachytherapy). Radical prostatectomy is more effective than radical external radiation therapy. Although radical prostatectomy is more effective, it is more invasive and not suitable for older patients, and the incidence of postoperative complications such as urinary incontinence and sexual dysfunction is higher; although radical external radiation therapy is less invasive, complications such as radiation proctitis and radiation cystitis are more common, and the clinical management of these complications is more difficult; complete androgen blockade therapy is only suitable for androgen-dependent tumors, and Complete androgen blockade therapy is only suitable for androgen-dependent tumors and has a large impact on sexual function, and anti-androgen drugs have effects on the liver. Brachytherapy has become the treatment of choice for many urologists abroad because of its minimal trauma and efficacy. As early as 1914, Pasteau first reported the treatment of prostate cancer with radioactive substances when radium-226 (226Ra) was implanted into the prostate gland with the aid of cystourethroscopy. 103Pd was discovered by Drs. P.V. Harper and Lathrop in the 1950s, and 125I was discovered by Lawrence in the 1960s, which In the early 1970s, 125I was sealed in a titanium shell and made into a “seed” of about 0.8×5 mm, which was implanted directly into the tumor tissue during open surgery. In 1981, Dr. Holm invented the technique of implanting nuclear particles into the prostate through a perineal puncture under transrectal ultrasound guidance, which was a **** in the history of brachytherapy. In the 1990s, the treatment planning system (TPS) was introduced to rationalize the distribution of radionuclide particles in the prostate. The high radiation dose to the tissues near the radionuclide particles and the rapid decay of the dose to the surrounding tissues allows the tumor to be irradiated at a high dose locally, but with less impact on the surrounding normal tissues. In this way, the surrounding organs are protected and the advantage of tumor tissues receiving continuous irradiation is maintained, which obviously improves the clinical effect and reduces the incidence and degree of complications. Particle implantation therapy for prostate cancer has just started in China, and the development of this technology requires the collaboration of multiple disciplines such as urology, radiation oncology, nuclear medicine and ultrasound. In order to master this minimally invasive treatment technology as soon as possible, to enrich the treatment of prostate cancer and to promote particle implantation therapy for prostate cancer in China, the Department of Urology of our hospital performed 5 cases of particle implantation therapy for prostate cancer from June 2002 to January 2003 in collaboration with related departments.