Three new indole alkaloids, 17-O-acetyl-N-b-demethylechitamine, echitamidine N-oxide and echitaminic acid, have been isolated from the stem bark of Alstonia glaucescens along with one iridoid compound, sweroside, and five known indole alkaloids, i.e. echitamidine, N-b-demethylechitamine, 20-epi-19 xi-echitamidine, N-b-demethylechitamine N-oxide and echitamine. Their structures were elucidated by spectroscopic methods, especially 2D NMR.