The invention relates to an arrangement in a tonometer, in which a probe (3) is brought into a contact with the surface of the eye and the intraocular pressure in the eye is derived from the variations in the velocity of the probe (3). The probe (3) is formed of a piece of a non-magnetic substance. The device includes a holder (4) located in the tubular component (1) and attached to a piece (6) providing the force for a measurement, in which holder (4) there are means (7) guided by the internal surface of the tubular component (1).
