Earlier studies have found that framing has a substantial impact on the degree of cooperation observed in public good experiments. We show that the way the public good game is framed affects misperceptions about the incentives of the game. Moreover, we show that such framing-induced differences in misperceptions are linked to the framing effect on subjects' cooperation behavior. When we do not control for the different levels of misperceptions between frames, we observe a significant framing effect on subjects' cooperation preferences. However, this framing effect becomes insignificant once we remove subjects who misperceive.