New potent tyroshase inhibitory cyclic peptides, pseudostellarins D - F, have been isolated from the roots of Pseudostellaria heterophylla and the structures were elucidated by extensive 2D NMR methods, chemical and enzymatic degradation and ES1 tandem MS spe&o~@c analysis.The roots of Aeua&&& heter&ylla are well known Chinese traditional medicine which are used as a lung and spleen tonic.2) During a survey of novel bioactive cyclic peptides from higher plants?) we have already isolated several peptidic compounds, showing tyrosinase inhibitory activity and melanin production inhibitory activities, from the roots of R heterophylla (Caryophyllaceae), and reported the structure of novel cyclic peptides, named pseudostelhuins A, B, C and G 1~4) As a result of our further bioassay guided fractionation efforts, three novel tyrosinase inhibitory cyclic peptides, named pseudostellarins D - F (1 - 3) have been isolated from the roots of R heterophykz. We report herein, the isolation, structure elucidation and the evaluation of tyrosinase inhibitory activities of analogous cyclic peptidic compounds (1 - 3).