A measuring apparatus, especially a measuring apparatus suitable for application in industrial process measurements technology for making measurements of physical or chemical, measured variables in a closed process container under increased pressure, comprising: a measuring probe, which has a probe shaft, especially a cylindrical probe shaft; and a securement apparatus to affix the measuring probe at a measuring point, wherein the securement apparatus comprises a sleeve, which at least sectionally accommodates probe shaft, wherein the measuring probe has a securement collar connected to the probe shaft; the securement collar is held, especially shape interlocked, between a coupling jacket releasably secured in sleeve and a counterbearing formed within sleeve, characterized in that, a first abutment surface is formed within the coupling jacket, and a second abutment surface, which lies opposite the first abutment surface, is formed on measuring probe.