Two new hetero-spirocyclic gamma-lactams, azaspirofurans A (1) and B (2), had been isolated from a marine sediment-derived fungus Aspergillus sydowi D2-6. Their structures were determined by the chemical evidence and spectral analyses. Compound 1 exhibited cytotoxicity against A549 cell line with the IC50 value of 10 microM by MTT method.