To provide a transpirator, capable of properly controlling the concentration of a transpired liquid in used space.

This transpirator is equipped with a transpiring liquid holder for impregnating a transpiring liquid, a transpiring means for properly heating and transpiring the transpiring liquid, a using state-changing over switch 5 for carrying out selection of using state and unusing state and an operating control means for carrying out the control of operation of the transpiring means. The transpirator alternately carries out transpiring action for operating the transpiring means by a primary prescribed time and a waiting action for stopping operation of the transpiring means by a secondary prescribed time by the operation control means when the using state is selected by the state- changing over switch 5. The transpirator is further equipped with an operation input means by which the primary prescribed time and the secondary prescribed time are set and a light-emitting part 8 which carries out turning on/off of fluorescence in the using state.