A measuring sensor, in particular, for determining the oxygen content in exhaust gases of internal combustion engines, includes a ceramic molding arranged in a metal housing for the accommodation of a sensor element, in particular, planar, the sensor element being sealed by a seal element made of warm-deformable temperature-resistant material. The molded housing is designed in one piece and has a cylindrically shaped longitudinal hole on the connector side, around the sensor element, and the seal element is compressed between a first compressing element on the measuring-gas side and a second compressing element on the connector side, such that it tightly encloses the sensor element and hermetically seals the sensor element with respect to the molded housing.