The invention discloses an anti-blocking flow switch comprising a switch base which is provided with a water inlet passage, a water outlet passage, a switch channel and a valve chamber. The switch channel is provided in a switch device. A valve body is arranged in the valve chamber. The anti-blocking flow switch is characterized in that a sealing isolation sheet is arranged between the valve chamber and the switch passage and used for separating the valve chamber from the switch passage. The advantages are that the valve body is separated from the switch device by the sealing isolation sheet so that the impurities and the dirt in the water flow are enabled not to contact the switch device, the blocking problem of the existing various flow switches in the use process can be fundamentally solved, the hidden trouble of the accident can be eliminated, the technical performance, the service performance, the service life and the economic benefit of the existing products can be remarkably improved and the environmental adaptability of the existing products can be greatly enhanced.