Objective To study the curative effect and prognosis of malignant pleural effusion treated by staphylotoxoid injection and its effect on immune system.Methods A total of 65 patients with malignant pleural effusion from August 2012 to 2014 November in Lishui City Central Hospital were selected,and divided into observation group(n=33) and control group (n=32) in terms of different treating methods,two groups were implemented with thoracic closed drainage to drain pleural effusion up.The observation group was completely drained after 2 500 U intrapleural injection of staphylotoxoid injection,the control group to the traditonal method of bleomycin 1 mg/kg injection.The efficacy,prognosis and immune system were compared.Results The effective of rate of the observation group was significantly higher(72.7%) than the control group(43.8%);the adverse reaction rate of observation group was lower and its median survival time was longer;white blood cells counts of observation group was significantly more than control group ( P<0.05).Conclusion Compared with the traditional method of bleomycin intrapleural injection treatment of malignant pleural effusion, staphylotoxoid injection can be more effective control of the disease , reduce adverse reactions, and can improve their immunity and improve the body tolerance .