The analysis in external morphology of Astilbe including three endemic species in Korea was undertaken. From this study, five species and three varieties of Astilbe in Korea were redescribed. Their scientific names and Korean names were also consulted. Korean Astilbe could be grouped in two Series-Series 1. Simplicifoliae; Astilbe simplicifoliae and Series 2. compositae; A. taquetii, A. microphylla, A. chiensis var. chinensis, A. chinensis var. paniculata, A. chinensis var. davidii, A. divaricata, A. koreana. Interspecific relationships of eight taxa were represented as a toxonomic model by the considering their external morphology-pubescence on floral axis and surface of leafblade, inflorescence type, ratio of petal and stamen length-and distributional range in Korea and neighboring countries.