To provide a crack inducing joint member which contributes to quick setting work thereof.

The crack inducing joint (10) is formed of: a main body (12) which is formed with a rectangular cross-sectional recess (16), and made of a resin material having an almost U-shaped cross section; a joint forming body (20) which has a foamed polyethylene portion fitted into the recess of the main body; and a fixing fastener (22) for fixing the main body to a form. The fastener has a nail (22a) having both sharp tips, and a rubber stopper (22b) for preventing the nail from slipping out.