68 cases of brain metastasis in lung cancer were treated from June 1987 to Dec. 1990. They were randomly divided into 2 groups. The first group was solely treated by radiotherapy and the second one, by radiotherapy adding with the intravenous injection of the 10% Brucea javanica emulsion. The results showed that the living quality and the prolonged median survival of the patients in the second group (15 months) were much better than those in the first group (10 months). The 10% Brucea javanica emulsion has synergetic with radiotherapy in treating brain metastasis in lung cancer.