The trend of organogenesis in Xenopus presumptive ectoderm was studied by combined dose of activin A and IGF-1(insulin-like growth factor-1). In reference study of Asashima and his colleagues, the inductive patterns of various organs were reported with activin, the potent mesoderm inducing factor. In present study, the inducing pattern was cleared with combined-dose of concentration 1-100 ng/ml activin A and IGF-1. In addition, the result from single treatment of activin A was compared with former study. As a result, eye was differentiated in 5-20% of explants at 10 and 50 ng/ml concentrative combination of activin A. Otic vesicle was appeared in the entire concentrative combination of IGF-1. Pronephric duct was induced 19-38% of explants at the concentration of activin A 100 ng/ml by adding IGF-1. The comparison of single treatment of activin A was showed some difference in dose-dependent inducing pattern.