To provide a measuring device, having compactness and high reliability for irreversibly measuring and displaying the temperature in units of 1/10C, in a very narrow temperature region of 99-100C.

A high-accuracy temperature recorder includes extending a slender tunnel-like slot 6 diameter-widening of the start end in the form of a funnel, from one part of the peripheral wall of a wax storing part 3 for enclosing a wax temperature sensitive body performing expansion and contraction, in response to the atmospheric temperature; filling the part near the start end of the slot; inserting a piston rod 10, from an open end side of the slot so that the edge abuts against the end face of a rubber-like fluid body; further, serially forming a piston rod guide groove in continuation, to the open end side of the slot; and adding a temperature scale that indicates the temperature by the movement position of the piston rod.