Abstract: A roof valley water diverter is provided herein for changing direction of rain water flowing through a roof valley. The diverter includes at least first and second side plates joined together to form a trough extending along a longitudinal axis and configured to channel a flow of rain water therethrough. A deflector plate, having opposing first and second faces, is secured to at least the first and second side plates such that the first face intersects the longitudinal axis. At least one gap is defined between the first face and at least one of the first and second side plates. Advantageously, the diverter of the subject invention allows for re-direction of flow of rain water from a roof valley.