Two new polycyclic polyprenylated acylphloroglucinols, along with four previously known compounds, were isolated and identified from the fruits of Garcinia oblongifolia. The structures of these compounds were elucidated through a combination of spectroscopic techniques, including MS, UV, IR, and 1D/2D NMR, as well as their chemical properties. Additionally, the cytotoxic activities of compounds 1‒6 against the H134B cell line were evaluated using the MTT assay, revealing that compounds 1 and 2 exhibit promising antitumor activity.