The present invention provides a dust sensor comprising: a sensor module for receiving light scattered by dust particles and outputting an electric signal; a communication module for communicating with an external device; a memory for storing region information in association with particle density data; and a control unit for calculating a volume of the dust particles based on the signal output from the sensor module, obtaining the region information for a location where the dust sensor is installed via the communication module, retrieving the particle density data corresponding the obtained region information from the memory, calculating dust concentration using the retrieved particle density data and the calculated volume, and outputting the calculated dust concentration. The memory may store the region information in association with air quality reference data.