One new coumarin compound, isopranferin (1), along with six known compounds 2-7, were isolated from Zanthoxylum nitidum. Their structures were determined on the basis of spectral data including 1D and 2D NMR and HR-EI-MS. Compounds 2-4, 6, and 7 were isolated from this plant for the first time. The in vitro cytotoxicity of compounds 1-7 to RAW264.7 cells, THP-1 cells, and Caco-2 cells was firstly tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods.