The disclosed device for trapping biologically-relevant substances can easily collect biologically-relevant substances from a thin tissue section or a gel in which said biologically-relevant substance have been fractionated. Said device is provided with: trapping bodies for trapping biologically-relevant substances; carriers that hold the trapping bodies; and electrodes for charging the trapping bodies. The trapping bodies are charged and brought into contact with a prescribed position on a thin tissue section that contains biologically-relevant substances or a gel in which biologically-relevant substances have been fractionated, thereby trapping said biologically-relevant substances from said gel or thin tissue section.