A new benzophenanthridine alkaloid, 6-[2'-ethoxy-2'-(2'',4'',5''-trimethoxyphenyl)] ethyl-7,8-dimethoxy-5-methyl-2,3-methylenedioxy-5,6-dihydrobenzo[c]phenanthridine named buesgeniine (1), as well as the known decarine, were isolated from the extract of the stem bark of Zanthoxylum buesgenii. In addition, three known lignans, sesamine, matairesinol dimethylether, and methylpluviatilol, were also identified. The structure of 1 was elucidated using spectroscopic methods.