Endophytic fungi from Aglaia argentea have indicated the prospective to produce secondary metabolites with unique activities, making them promising candidates for anticancer drug development. This study aimed to investigate the secondary metabolites produced by Lasiodiplodia theobromae BPPCA144, isolated from A. argentea. L. theobromae BPPCA144 was found to produce seven compounds: 2-phenylethanol (1), tyrosol (2), 2-(4-hydroxyphenyl)acetic acid (3), (-)-mellein (4), colletopeptide B (5), botryorhodine A (6), and (4R*,6R*)-4-hydroxy-6-n-propyl-1-oxacyclohexan-2-one (7). These compounds were isolated using vacuum liquid and radial chromatography, and their chemical structures were elucidated through 1D-NMR, 2D-NMR analysis, compared with previously reported spectral data. Notably, compounds (5) and (7) were identified as original from L. theobromae. Among the tested compounds, compound (2) exhibited the strongest activity against MCF-7 breast cancer cells. However, compounds (1, 3, 5 and 7) showed insufficient activity against CV-1 cell lines (normal kidney fibroblast cells).