摘要Objective: The aim of our study was to explore the short-term effects and complication of interleukin-2 (IL-2) combining with Cisplatin in the treatment of malignant hydrothorax. Methods: Sixty-two cases patients with malignant hydrothorax were randomly divided into two groups. Observation group was 31 examples, thoracic cavity injection IL-2 and Cisplatin; 31cases in control group using Cisplatin alone intra-thoracic injection. The regime of every week for 1-4 weeks was used to observe short term effects and complications. Results: The total response rate in observe group was higher than that in control group (90.3% vs. 68.1%), which had statistically significant difference (P ＜ 0.05). The complications included gastrointestinal tract reaction, bone marrow inhibition, chest pain and fever. The incidence rates of chest pain and fever in observe group was slightly higher than that in control group, but there was no statistically significant difference (P ＞ 0.05). Conclusion: The IL-2 combining with Cisplatin intra-thoracic injection for malignant hydrothorax has the features of good therapeutic effects and slight poisonous side effects, which is worth to be used in clinic.