The adhesion forces of polymer particles to aluminum substrates were measured by the electric field detachment method. Conductive polymer particles were used for the measurements. When measuring the adhesion forces, some particles were spattered over on one of a pair of parallel aluminum electrodes. The DC voltage applied to the electrode was increased at a constant rate, and the occurrence of the particle detachment was observed by measuring the current flowing between the electrodes. The adhesion forces of measured particles were estimated from the voltage at the occurrence of the particle detachment. The numbers of particles, which have a certain adhesion force, were estimated from the voltage and current. The influence of particle size, surface roughness of aluminum substrate, etc. on the particle adhesion forces was examined. The adhesion force of polymer particle increased with an increase in particle size and time elapsed after adhesion. The surface roughness of the substrate strongly influences on the particle adhesion force. The mechanism of particle adhesion will be discussed.