To enable stable gas pressure detection with high accuracy and reliability by reducing the variation in a stress absorbing property of a pressure sensor element (diaphragm film).

A pressure sensor element 1 is molded integrally with a lead frame 3 and a pressure introducing pipe 4 through a gas resistant adhesive agent 2. The gas resistant adhesive agent 2, even when subject to step cure hardening, does not realize 100% completed hardening. By reducing the unhardened portions, output variation can be prevented. Portions contacting measured fluid (LP gas, city gas) is constituted of a gas resistant rubber seal material 7 and a gas resistant adhesive agent 2, so that the material can be prevented from degradation. Also, by step curing the hardening method for the gas resistant adhesive agent 2, a process for high temperature hardening can be realized after the filled gas resistant adhesive agent 2 is hardened in low temperature in a short time, and an advantageous effect on the estimation of the thickness and the reduction of stress by cold cure is obtained.