A mass flow Internet of Things sensor, comprising: a flow pathway, an air inlet (1) and an air outlet (9); an upper portion of the flow pathway is a buoy (11), the buoy (11) being provided therein with a float group; the float group consists of a plurality of floats (6, 7, 8, 12), and the floats (6, 7, 8, 12) are nested in order from large to small, the largest float (6) being located at a bottom portion of the buoy (11); the flow pathway is provided therein with a resistance strain gauge (4). The floats (6, 7, 8, 12) in the float group float under the action of airflow, triggering the resistance strain gauge (4) to change shape, and a micro change in mass is obtained by means of the amount of change in the resistance strain gauge (4), a flow speed signal of a fluid being obtained by means of single-chip microcomputer operation; the resistance strain gauge (4) is connected to an input end of a Wheatstone bridge, while an output end of the Wheatstone bridge is connected to an input end of the single-chip micro
