Two novel phenethylamine alkaloids were isolated from Streptomyces sp. YIM 10049. On the basis of spectral data, their structures were determined as (S)-N-(α-phenylethyl)-2-hydroxyl-acrylimine (1) and (S)-N-nitroso-1-amino- p-hydroxy phenylethanol (2). Three known compounds, indole-3-carboxylic acid (3), cyclo(L-Ala-L-Tyr)(4), and bis(2-ethylhexyl) phthalate (5), were also isolated and characterized. Compound 1 is a rare enol tautomer, and compound 2 an unusual phenethylamine alkaloid with a N-NO group.