Disclosed in the present invention are a bis-β-carboline compound and a preparation method, a pharmaceutical composition and the use thereof. In particular, the bis-β-carboline compound and a pharmaceutical salt thereof are described as general formula I, and the bis-β-carboline compound is prepared through the condensation of β-carboline intermediate and dihaloalkane. Also disclosed in the present invention are a pharmaceutical composition comprising an effective dose of the bis-β-carboline compound as shown in formula I and a pharmaceutically acceptable carrier, and the use of the bis-β-carboline compound in preparing drugs resistant to tumors such as melanoma, stomach cancer, lung cancer, breast cancer, kidney cancer, liver cancer, oral epidermoid carcinoma, cervical cancer, ovarian cancer, pancreatic cancer, prostate cancer, and colon cancer.