The phytochemical investigation of extracts from the roots of Asparagus cochinchinensis yielded a new indole alkaloid dimer, N-methyl-2,2'-ditryptamine (1), and a known beta-carboline alkaloid, (-)-(1S,3S)-1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (2). Their structures were established on the basis of spectral data, particularly by the use of 1D NMR and several 2D shift-correlated NMR pulse sequences (H-1-H-1 COSY, HSQC and HMBC).