PURPOSE: A microorganism carrier for high-performance bioreactor, comprising ceramic having primary pores with large diameters and secondary pores with small diameters.

CONSTITUTION: A microorganism carrier comprising ceramic having primary pores 11 with 1W3mm average diameter and secondary pores 12 with 10W150μm average diameter. The microorganism carrier, for example, is obtained by blending alumina powder having ≤20μm particle diameter with water, a urethane system with 5W15% based on the total amount of a blowing agent of two-part liquid system, molding into a desired shape and sintering. Various foams are generated by the action of the blowing agent, small foams are attached to peripheries of large foams and ceramic having desired pores 11 and 12 can be produced.