BACKGROUND:: Pneumocystis carinii pneumonia is a serious complication after renal transplantation. It is rare and onset is insidious. A typical clinical symptoms, rapid progression and high mortality are observerd in this desease. OBJECTIVE:: To investigate the clinical features, treatment and prevention methods of pneumocystis carinii pneumonia after renal transplantation. METHODS:: The clinical data of one case of severe pneumocystis carinii pneumonia after renal transplantation that selected from the First Affiliated Hospital of Xiʼan Jiaotong University School of Medicine were retrospectively analyzed. RESULTS AND CONCLUSION:: A 62-year-old female kidney transplantation recipient suffered from fever and progressive hypoxemia at 100 days after the transplantation. Pneumocystis carinii pneumonia was detected by bronchoscopy and alveolar biopsy. Through compound sulfamethoxazole and trimethoprim tablets administration, mechanical ventilation and other supportive treatment, the patient was cured. Prevention is particularly important in pneumocystis carinii pneumonia because the rapid progression and high mortality. Bronchoscopy should be carried out early in the patients with risk factors especially those have presented clinical symptoms such as fever and hypoxemia. Immunosuppressive agents should be adjusted carefully in the course of treatment of pneumocystis carinii pneumonia. The ratio of CD4/CD8 may be a useful index to the adjustment of immunosuppressive agents.(Figure is included in full-text article.)