Since tropical rainfall is important in the global energy and hydrologic cycle, the tropical rainfall changes under global warming arise extensive attention around the world in recent decades. The advances in the observational studies and model projection for the tropical rainfall changes under global warming are reviewed here. The frontiers in the mechanism of regional tropical rainfall changes and the approaches of rainfall change research are summarized. The large intermodel spread in the multi-model projections, the sources of uncertainty and the methods to reduce the uncertainty are also introduced. In the last, the challenges about the tropical rainfall changes are discussed.