Kaempferia simaoensis, another precocious floweringspecies of Kaempferia subg. Protanthium (Zingiberaceae) from Kanchanaburi and Tak,Thailand is described. This new record species is closely similar to K. rotunda, but itis characterized by narrowly ovate anther crest with obtuse to shallowly 3-lobed apex, the middle lobemore elongated than outer lobes and prominent yellow patch from the center to base oflabellum. Moreover, phylogenetic analyses based on ITS2 sequences supported themorphological studied and indicated that K. simaoensis is obviously different from K.rotunda.