Although the ROC's insistence on claiming sovereignty over Nansha (Spratly) Islands, in fact, it can not be ignored that some islands have been occupied by other claimants. This paper analyzes those International Court of Justice (ICJ) judgments corresponding to sovereignty disputes after 1990's, and selects "Land, Island and Maritime Frontier Dispute. El Sal./Hond.: Nicar." of year 1992, "Sovereignty over Pulau Ligitan and Pulau Sipadan. Indon. v. Malay." of year 2002, "Sovereignty Over Pedra Brance/Pulau Batu Puteh, Middle Rocks and South Ledge. Malay. v. Sing." of year 2008, and "Territorial and Maritime Dispute. Nicara. v. Colom." of year 2012, to examine the critical elements adopted by international court of justice. With those critical elements this paper also reviews the current sovereignty claims of R.O.C over Nansha Islands and provides some useful suggestions in that sense.