A fingerprint detecting agent and a fingerprint detecting method using the agent, which can be used to detect latent fingerprints being in a wet condition, the fingerprint detecting agent includes a fixer containing silicone series compound, fluoride series compound, hydrocarbon series compound, animal or vegetable oil, higher fatty acid, or higher alcohol, and an arbitrary mixture thereof; a diluent containing polar soluent; a developer containing achromatic colored powder or chromatic colored powder. Latent fingerprints can be easily detected by spraying the fingerprint detecting agent; particularly, even if the latent fingerprints to be detected are in a wet condition, it is possible to detect them speedily and certainly.