In our previous studies, four stevastelin congeners named A, B, B3 and C3 have been isolated from culture broth of a fungus, Penicillium, as immunosuppressants1}. Structures of these stevastelins have been elucidated to be cyclic depsipeptides2'3). In the course of ultraviolet treatment of the strain, we found that a high producing mutant yielded three novel stevastelin congeners. In this report we describe isolation, physico-chemical properties, structural elucidation and immunosuppressive activities of these novel stevastelin congeners named A3, D3 and E3.