PROBLEM TO BE SOLVED: To provide a chemical supply device and a water flow type fish testing apparatus that can execute a water flow type fish test without requiring a solvent control trial.SOLUTION: A water flow type fish testing apparatus comprises: chemical supply means that supplies a chemical to a test water tank for keeping a sample using test water which is mixture of a chemical and dilution water; and dilution water supply means that supplies the dilution water to the test water tank. The chemical supply means comprises: a water tank for the chemical; a holding member that is provided in the water tank for the chemical, can hold a test substance and enables water to pass through; flowing means that enables water in the water tank for the chemical to flow; and supply means that can supply the chemical generated in the water tank for the chemical to the outside of the water tank for the chemical.
