Color wheel module and projection device

A color wheel module comprises a driving assembly, a substrate, a first wavelength conversion layer and a second wavelength conversion layer. The base plate is connected to the rotating shaft of the driving assembly, and the driving assembly drives the base plate to rotate with the rotating shaft of the driving assembly as the center axis. The substrate comprises an outer wall surrounding a central shaft and a first disc surface perpendicular to the central shaft, and is provided with a first light conversion area located on the outer wall and a second light conversion area located on the first disc surface. The extension direction of the outer wall forms an included angle with the radial direction of the substrate and has a width parallel to the extension direction. The first and second wavelength conversion layers are disposed in the first and second light conversion regions, respectively. The first excitation light beam enters the first light conversion area in the direction perpendicular to the central ax