The interactive projection system for walls connects a projector with an infrared sensing module, capturing the participant's movements with the capturing device, and integrates with an interactive system to create a tightly coupled interactive effect with the wall. The screen can be a screen or an LED splicing screen, and it can be front or rear projection; the projector can also be front or rear projection, usually choosing an engineering projector or a super short-throw projector to avoid the participant's shadow blocking the projection light, enhancing the audience's enthusiasm for participation, and making it easier to gather a crowd.