The authors report on the fabrication and operation of a real-time dust particle sensor using a paddle-type silicon cantilever. Electrostatic field applied to the cantilever electrode attracts dust particles, and as they attach on the paddle surface the oscillation phase changes, reflecting the particle mass. The kinetic energy of the oscillating cantilever limits the size of the dust particle landing on its surface at the given electric field, controlling the maximum mass, and therefore the size, of the dust particles being detected. The measurement of a single dust particle of similar to 1.2 pg attaching and detaching from the oscillator surface was demonstrated. The results show that the paddle-type cantilever sensor may be developed into a real-time monitoring sensor of airborne submicron dust particles.