Cordyceps guangdongensis is a species found in South China not long ago. It has been successfully cultivated. Previous studies indicated that the fruiting body of the fungus has noticeable effects of anti-oxidation, anti-H9N2 virus, anti-fatigue and life-prolonging, but its effect on treatment of renal disease has not yet been reported. In this study, therapeutic effects of the fungus on chronic renal failure (CRF) rats were tested. The CRF rat model was induced by feeding adenine, and the rats were divided into 6 test groups, a blank control group without any medicine treatment, a positive control group treated with a Chinese patent medicine ‘Niaoduqing’, a normal control group of healthy rats and 3 treatment groups fed respectively with low dose, middle dose or high dose of the fruiting body of C. guangdongensis. The levels of rat blood urea nitrogen (BUN), creatinine (Cr), amount of emiction within 24h, urinary protein (UP) and pathological reaction of nephridial tissue were rountinely investigated with Creatinine (Cr) kit, blood urea nitrogen（BUN）kit, albumin (ALB) kit, total protein (TP) kit and urinary protein (UP) kit and standardized approaches. The results were analyzed through comparisons of the tested data from different groups of CRF rats as well as from the normal control group of healthy rats. The results showed that feeding C. guangdongensis fruit body could improve the renal functions and reduce the BUN and Cr of the CRF rats, promote the body to generate albumin (ALB) and total protein (TP) to make up the proteins that were partially lost owing to renal damage, and alleviate the renal pathological changes of CRF rats. The conclusion can be drawn that the fruiting body of C. guangdongensis has prominent therapeutic effects on CRF rats.