Dew point sensor

The utility model discloses a dew-point sensor, which relates to the technical field of sensors and can filter dust in gas and then detect the gas, so that the detection precision of the dew-point sensor is improved, and the service life of the dew-point sensor is prolonged. A dew point sensor comprises a base, a sleeve, a sensor chip and a filtering device. And the sleeve is screwed on the base. And a first cavity is formed in the sleeve. The sensor chip is arranged in the base and is communicated with the first cavity. The filtering device is contained in the first cavity and connected with the base. And external gas is filtered by the filtering device and then is measured by the sensor chip. According to the technical scheme, before external gas is in contact with the sensor chip, the external gas is firstly filtered by the filtering device, so that most impurities can be filtered, the influence of impurities, dust and the like on the sensor chip is further reduced, the accuracy of a detection result is gr