Aphapolin A (1), a nemoralisin-type diterpenoid possessing a unique 4/5 fused ring system that is unprecedented in previously reported nemoralisin diterpenoid, and aphapolin B (2), a novel nemoralisin-type diterpenoid derivative containing a benzofuran moiety, along with a new nature product compound 3, were isolated from Aphanamixis polystachya (Wall.) R.Parker. Their structures and absolute configurations were elucidated by spectroscopic data, X-ray crystallography diffraction analysis as well as calculations of electronic circular dichroism (ECD). The plausible biosynthetic pathways of compounds 1 and 2 are also described.