To enlarge the range of applicable fluids and conduct an accurate evaluation of performance of a solid catalyst by the continuous supply of liquid raw materials or mixed raw materials of gas and liquid from a raw material supplying part.

A raw material supplying part 1 for supplying liquid raw materials has a function to continuously supply liquid raw materials or mixed raw materials of gas and liquid. A reaction part 2 comprises a reactor 20 and brings a liquid raw material supplied from the supplying part 1 via a gas-liquid supply pipe 11 into catalytic reaction with a solid catalyst 23 arranged in the reactor 20. A liquid level control part 30 communicates with the liquid phase and gas phase of a reaction product discharged from the reactor 20 and maintains a liquid level in the reactor 20 constant. The reaction product separated into gas and liquid at a gas-liquid separating tank 35 is introduced to an evaluating part provided for flow-rate measurement, composition analysis, etc., via a pressure controlling valve 37 and a cooler to perform the evaluation of the solid catalyst. The reaction product is continuously extracted from a recovery part 3 to perform the evaluation of the catalyst according to desired evaluation conditions.