The invention relates to an implantable measuring device (1) for measuring the intraocular pressure at an ocular sclera (2), having pressure sensor means (5, 7) embedded in a pressure-transmitting housing (6) for biocompatible contacting of the ocular sclera (2), having at least one, preferably substantially flat, pressure sensor area (7) that allows for a reliable measurement of the intraocular pressure and is operatively easy to insert, in as much as possible, while avoiding the disadvantages of the prior art, wherein it is proposed that the housing (6) is configured with dimensionally stable elasticity.