By　using　plasma-assisted　radio-frequency　molecular　beam　epitaxy,　the　influence　of　substrate　surface　preconditiong　and　growth　temperature　on　in-plane　and　polar　orientations　and　surface　morphology　of　ZnO　thin　films　on　LSAT(111)　substrates　are　investigated.　Rotation　domains　are　observed　in　ZnO　film　grown　at　low　temperature,　while　single-domain　O-polar　ZnO　has　been　obtained　with　oxygen　radicals　pretreatment　and　high　growth　temperature.　The　origin　of　rotation　domains　in　ZnO　thin　film　is　also　discussed.