The Marsh Gladiolus, Gladiolus palustris is a Central-European geoelement that extends its distribution to Albania, Bulgaria and North Macedonia at the Balkan Peninsula. It has a local distribution and inhabits marshes and wet meadows. It is included in Annex IIb of the Council Directive 92/43 EEC. There are insufficient data for its populations across the areal. Thus, it is considered as Data Deficient in the European Red List of Vascular Plants. Only singular, old dated reports existed for Bulgaria at the beginning of this century. More data were collected during the processes of designation of the Important Plant Areas and Natura 2000 SACs in the country (2004–2013). Here we summarize and discuss the data about the distribution in Bulgaria and the existing data for the known populations. Nowadays the distribution in two floristic regions (Pirin Mt. and Rhodope Mts.) is confirmed; there is no recent confirmation for the localities in other two regions (Rila Mt. and Slavyanka Mt.). Populations’ densities and numbers are highly variable, from less than 50 to thousands of individuals. We discuss the habitats and their management. The most important negative factor is the abandonment of the meadows.