This detection device has a holder and a heating unit. The holder holds a detection chip that has the following: a prism that has an incidence surface and a film-formation surface; a metal film formed on said film-formation surface; trapping bodies laid out on the surface of said metal film; and a substrate that is laid out on the surface of the metal film, and together with the metal film, forms a liquid collection section in which a liquid is collected. The heating unit heats at least one of the substrate, the prism, and the metal film either while in contact therewith or without contacting same. Also, the heating unit is positioned so as to avoid the path that excitation light takes from an excitation-light emission unit to the abovementioned incidence surface.