Eight new tetramic acid derivatives, cladosporiumins AeH (1e8) were isolated from a culture broth of Cladosporium sp. SCSIO z0025 derived from the deep-sea sediment collected from Okinawa Trough. Their structures were elucidated by extensive spectroscopic data analysis. Compounds 1e3 were unique 3 acyltetramic acids with a hexyl enic alcohol side chain and a six-membered lactone ring substituted at C-3 of the 2, 4-pyrrolidinedione skeleton. The absolute configurations of chiral carbons of the 2, 4 pyrrolidinedione unit in 1e4 and 7 were established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. And the absolute configurations of chiral carbons of the sixmembered lactone ring in 1e3 were established by density functional theory calculation of their 13C NMR chemical shifts. In addition, all the compounds were tested for cytotoxic, antibacterial, anti-biofilm, and AchE inhibitory activities.