A measurement technique for the charge on a single toner particle using nanotweezers (microelectromechanical-systems-based actuated tweezers) and an atomic force microscopy cantilever has been developed. This unique system was designed to measure the image force on the cantilever induced by a charged toner particle gripped by nanotweezers. The toner charge was estimated from the image force by modeling the nonuniform charge distribution on the particle as an imaginary point charge. The comparison of the charges of single toner particles is possible because the calculated charge showed a linear correlation with that obtained using the blow-off method. This technique has great potential for application to the analysis of single isolated toner particles, such as those in fogging or transfer dust toner.