Abstract: An electromagnetic wave induction device using smoke instead of antennas and a switch using the same adopt the smoke to realize the induction of the electromagnetic wave signal, and the smoke replaces the antenna as the receiving device, which is not susceptible to the environment and can be applied to occasions where antenna is limited. Smoke can reduce the safety hazard caused by the antenna, and can be recognized by the naked eye, so as to intuitively read signal transformation and realize the visualization of electromagnetic wave signal induction. Compared with the conventional electromagnetic wave induction device, the present invention provides a brand-new electromagnetic induction device. The antenna of the receiving portion is replaced by the smoke in the experimental cavity, and the smoke is directly used as a signal receiving device, which overcomes the antenna constraints in prior art.