PURPOSE: To improve the electrostatic chargeability, wear resistance, water repellency and electrostatic charge stability of a carrier by coating the surface of the carrier with a hydrocarbon-based plasma-polymerized film contg. fluorine and a metal.

CONSTITUTION: The surface of a carrier is coated with a hydrocarbon-based plasma-polymerized film contg. fluorine and a metal. For example, parallel flat electrodes 12 are arranged in a bell jar 11, a plastic vessel 14 contg. carrier powder 13 is put on the lower electrode 12 and brought into contact with a vibrating bar 15 and vibration is applied to the entire vessel 14 with a vibrator 16. High frequency power is supplied to the electrodes 12 to generate plasma and a monomer introduced into the bell jar 11 is plasma-polymerized. Since the carrier powder 13 is always under convection, the surface can be uniformly coated with the plasma-polymerized film. Thus, the electrostatic chargeability, electric resistance, wear resistance and water repellency of the carrier can be improved.