The present invention provides a novel process for the preparation of (lR,2R,3aS,9aS)-[[2,3,3a,4,9,9a-Hexahydro-2-hydroxy-l-[(3S)-3-hydroxyoctyl]-lH-benz[f]inden-5-yl] oxy]acetic acid represented by structural formula-1 and its pharmaceutically acceptable acid addition salts, preferably its sodium salt represented by structural formula-la.