S-Acetyl-3'-deoxyadenosine, a new nucleoside derivative, has been isolated from Emericella nidulans var. lata, together with 3'-deoxyadenosine (cordycepin). Emericella nidulans (Eidam) Vuill. var. lata (Thorn & Raper) Subram. (anamorph: Aspergillus nidulans Samson & W. Gams), strain IN-68 is an ascomycetous fungus isolated from the Indonesian medicinal plant, Tinospora tenuifolia L., used as carminatives and tonic medicine [1]. We report the structure of a new nucleoside derivative (1) isolated from the ethyl acetate extract of the rice cultures of this fungus, along with 3'-deoxyadenosine (cordycepin) (2) [2, 3].