The effect of charged dust on the Farley-Buneman instability is investigated. Linear kinetic theory is used to estimate the critical electron drift in the presence of either negatively or positively charged dust. The charge-to-mass ratio of the dust is much smaller than that of the ions, and the dust influences the instability through its effect on equilibrium charge neutrality. It is shown that in certain regimes, the critical drift can decrease as the charge density carried by negatively charged dust increases. Possible application to dusty plasmas in the upper D/lower E region boundary region of the Earth's ionosphere is discussed.