Wavelength conversion module and projection device

The invention provides a wavelength conversion module. The wavelength conversion module comprises a driving assembly, a substrate, a light-transmitting plate and a wavelength conversion layer. The driving assembly is connected with the substrate and drives the substrate to rotate around the center of the substrate. The substrate is a metal substrate and comprises a first concave-convex structure and a second concave-convex structure, and the substrate, the first concave-convex structure and the second concave-convex structure are integrally formed. The first concave-convex structure and the second concave-convex structure are arranged around the center of the substrate, and the second concave-convex structure surrounds the first concave-convex structure. The substrate is provided with a first balance hole and an accommodating groove. The first concave-convex structure is located between the containing groove and the center in the radial direction of the substrate. The first balance hole is located in the cont