To provide a connecting fitting capable of preventing imperfect connection (intermediate state between connection and release) and preventing galling phenomenon between a liner part and a joint part.

At least, one of connecting fitting bodies 31a and 31b is provided with the liner part 35a having a seal surface and a fitting part with a hose or a pipe element, multiple fitting projections 8 and recesses 7, and a joint part 34a rotatably fitted to the outside of the liner part 35a. This connecting fixture is characterized in that when the inside diameter of the joint part for fitting the liner part is set to N, the outside diameter of the liner part for being fitted in the joint part is set to G, the rotation angle of a clearance in releasing a lock claw part 9 of the joint part is set to β, and, when the liner part and the joint part are mutually deviated diametrically with the liner part fitted in the joint part, a clearance formed between the outer circumferential surface of the liner part and the internal circumferential surface of the joint part is set to S, the relation between these values and the clearance S is N-G=S and S<(πNβ/360°).