To provide a piping connection device, equipped with an adherend detector capable of directly fixing the detector for detecting the adherend in piping to the inside of the piping, without having to apply perforation processing or a pipe drawing process on existing pipings, and has a constitution that will not allow gas flowing through the piping to leak to the outside to the outside, and is equipped with the detector in the piping that takes into consideration the maintenability.

The piping connection device 10 is constituted so that O-rings 3 and 3 between the flange edge faces 1a and 1a of a pair of the piping and a center ring 2 develop a tight sealing, in a state with the detector 30 clamped by a clamp 20 and inserted into the through-hole 6 of the center ring 2, such that the O-ring 4 between the flange part 31 of the detector 30 and the center ring 2 exhibits a tight sealing by the pressing part 21 attached to the clamp 20.