To obtain an electrostatic separator in which the throughput of powder containing granular material is sharply increased by improving maintainability of an electric field applied space to sharply reduce cleaning work time and lost labor and also continuous operation for many hours can be performed to improve treating efficiency.

This electrostatic separator is constituted of a powder treating vessel C and a powder recovery vessel D. In the powder treating vessel C, a powder feeder 21 and a powder separator 20 are installed. The powder separator 20 is constituted of a high voltage electrode 22 arranged fixed thereto and a drum electrode 23 provided arranged opposite to the high voltage electrode 22. The drum electrode 23 can be removed and replaced with a new one.