Investigation of the ethyl acetate-soluble layer from the liquid fermentation of Phomopsis asparagi, an endophytic fungus isolated from the Taiwanese endemic plant of Peperomia sui T.T. Lin & S.Y. Lu, led to the isolation of a new cytochalasin, phomocytochalasin A (1), and one benzenoid, phomoaspardiol (2), which was isolated from nature for the first time, along with eight known compounds including two cytochalasins, four benzenoids, one chromone, and one steroid. The structures of the isolates were established by spectroscopic methods, including UV, IR, HR-ESI-MS, and extensive 1D and 2D NMR techniques, as well as by comparison with literature reports. Among the isolates, cytochalasin J showed androgen receptor (AR) antagonism with the IC50 value of 6.20 M.