The present study was designed to identify bioactive compounds similar to those isolated from Dendrobium genus from its relative specie Eria bambusifolia. Compounds 1–10 were isolated and purified using silica gel, MCI CHP-20 gel, Sephadex LH-20, and Lichroprep RP-18 chromatography methods. Their structures were elucidated by means of extensive spectroscopic analyses. The cytotoxicity of these compounds against five human cancer cell lines was tested. Erathrins A and B(1 and 2) were new compounds, and compound 1 represented a novel carbon framework having a phenanthrene-phenylpropane unit with a dioxane moiety. Moreover, compound 1 showed selective cytotoxic activity against HL-60 cells(IC_(50) = 14.50 μmol×L^(–1)). These results provided a basis for future development of these agents as anticancer lead compounds.