Provided are a wavelength conversion apparatus, a light source system including the same, and a display device including the light source system. The wavelength conversion apparatus includes an angle deflection region and a wavelength conversion region for converting incident second light into excited light and then emitting same. The angle deflection region includes deflection units, each of which includes a light emergent face for emitting first light. A first included angle is formed between the light emergent face and a reference plane. First included angles between light emergent faces of at least two deflection units and the reference plane are not equal. The deflection units are located on a light path of the first light in a time sequence, so as to change an emergent angle of the first light in the time sequence, such that the first light is successively scanned at a preset position to form virtual pixels.