Spicarins A (1) and B (2), two novel isobenzfuran-aspochalasin heterodimers, and spicarins C (3) and D (4), two isobenzofuran dimers, were isolated from the acetylated products of the marine-derived fungus Spicaria elegans KLA03. The structures of compounds 1-4 were elucidated by spectroscopic and/or Xray diffraction methods. Compounds 3 and 4 inhibited lipopolysaccharide (LPS)-induced nitric oxide production in BV2 microglial cells.