The taxonomy and distribution of Kaempferia subgen. Protanthium (Zingiberaceae) in Myanmar remain incompletely documented despite the botanical significance of the region. This study aims to clarify the diversity and taxonomic status of species belonging to this subgenus in Myanmar through field investigations and herbarium studies. Detailed morphological examinations of newly collected and previously documented specimens were conducted to evaluate diagnostic characters and species delimitation. As a result, Kaempferia kayinensis is described in this paper as a new species from Kayin State, southeastern Myanmar, and K. simaoensis Y.Y.Qian as a new country record. In addition, the taxonomic status of K. parishii Hook.f. is reassessed and reinstated based on morphological evidence, distinguishing it from K. ovalifolia Roxb. These findings confirm the presence of four species of Kaempferia subgen. Protanthium in Myanmar (K. kayinensis, K. parishii, K. rotunda, and K. simaoensis) and increase the number of known Kaempferia species in the country to twelve. The results highlight the importance of continued floristic and taxonomic studies to better document the diversity of Kaempferia in Myanmar.