A ceramic heat exchanger includes a heat exchange section that heat-exchanges between two fluids A and B flowing opposite directions to each other. The heat exchange section includes ceramic blocks stacked one on top of another with a seal therebetween. The ceramic blocks have a plurality of parallel lines of flow channels, each line defined by the flow channels through which the same fluid flows, any two adjacent lines being defined by the flow channels through which the different fluids A and B flow respectively. Both ends in the stacking direction of the stack are bound to join and integrate the ceramic blocks with tightening means including end plates and a tie rod. A thermal expansion absorber is disposed on an external surface of the end plates for absorbing thermal expansion in the axial direction of the tie rod.