A contact state estimating device (1) which determines whether a measuring device for measuring a biological signal or the like is in a state of contact or a state of non-contact with respect to an object being measured is provided with: a first electrode (10a) and a second electrode (10b) which are brought into contact with an object being measured such as a living body； a direct current voltage supply unit (2)； a signal switching unit (3) which switches between a first pathway whereby the direct current voltage supply unit (2) supplies a direct current voltage to the first electrode (10a) and an output signal from the second electrode (10b) is output, and a second pathway whereby the direct current voltage supply unit (2) supplies a direct current voltage to the second electrode (10b) and an output signal from the first electrode (10a) is output； and a contact state estimating unit (8) which estimates the state of contact of the first electrode (10a) or the second electrode (10b) with respect to the object being measured, on the basis of an output signal acquired at a time at which it is anticipated that pulse-type noise will occur concomitant with a signal switching operation to switch between the first pathway and the second pathway.L'invention concerne un dispositif d'estimation d'état de contact (1) qui détermine si un dispositif de mesure destiné à mesurer un signal biologique ou similaire se trouve dans un état de contact ou un état de non-contact par rapport à un objet mesuré, comprenant : une première électrode (10a) et une seconde électrode (10b) qui sont mises en contact avec un objet mesuré tel qu'un corps vivant ； une unité d'alimentation en tension continue (2) ； une unité de commutation de signal (3) qui commute entre un premier trajet, l'unité d'alimentation en tension continue (2) alimentant la première électrode (10a) en tension continue et un signal de sortie provenant de la seconde électrode (10b) étant délivré, et un second trajet, l'unité d'al
