To provide a measuring apparatus which enables the evaluation of characteristics in a single material body with easier sampling free from effect of particle characteristics while allowing evaluation of a saturation electric charge value and rising characteristic of the charging and moreover, evaluation of charging phenomenon corresponding to the patterns of contact and separation as charging phenomenon.

This apparatus is provided with a sample holding roller-shaped electrode 2 having a sample layer 1 on the surface thereof, a reference substance holding roller-shaped electrode 4 having a reference substance layer 3 on the surface thereon, a roller-shaped electrode holding member 5 allowed to support the roller-shaped electrodes 2 and 4 free to rotate, a frame base 6 comprising an insulating member as base for supporting the roller-shaped electrode member 5 and an electric charge measuring device 7 to measure the electric charge generated in a sample layer 1 or the reference substance layer 3. The sample holding roller-shaped electrodes 2 and the reference substance holding roller-shaped electrode 4 are arranged to be parallel with each other in the axial directions thereof while the sample layer 1 and the reference substance layer 3 contact each other and the electric charge generated when both the layers turn is measured by the electric charge measuring device 7.