Atractylodimers A-D (1-4), sesquiterpenoid dimers fusing a unique cage-like scaffold, were isolated from Atractylodes macrocephala. Particularly, 1 possessed a furo[2,3b]furan ring and caged 3,10-oxa-tricyclo[5.2.1.04,9]decane moiety. 4 contained a caged spiro-2,5,9-oxa-tricyclo[5.2.1.04,10]decane structure. Their structures were unambiguously established by X-ray diffraction experiments. The plausible biosynthetic pathways were proposed. 1 and 2 showed significant neuroprotective effects against serum deficiency-induced PC12 cell damage.