Abstract. Let S be a real semisimple Lie group with Lie algebra s = k + p. The Kostant-Sekiguchi correspondence is a bijection between nilpotent S orbits on s and nilpotent K C orbits on p C . In this note we prove that the closure relations among nilpotent orbits are preserved under the KostantSekiguchi correspondence. The techniques rely on work of M. Vergne and P. Kronheimer.