The　long-term　volume　changes　of　Portland-Calcium　sulfoaluminate　cement　systems　has　been　studied　for　samples　cured　under　different　conditions.　Three　curing　conditions　were　chosen　in　this　study　and　the　composite　cement　systems　showed　different　results　with　different　CSA　dosages.　Progressively　higher　amount　of　CSA　was　added　to　the　composite　cement　system　and　it　was　found　that　there　was　a　critical　dosage　of　CSA　leading　to　unstable　expansion　and　failure　of　the　samples　by　curing　under　water.　But　in　drying　condition,　the　systems　showed　shrinkage　and　the　degree　of　volume　changes　were　similar　than　expansion　by　curing　under　water.　By　selecting　the　composition　of　CSA-PC　systems　and　curing　conditions,　the　volume　stability　of　composite　cement　could　be　controlled.