An improved structure bolt snap in which a rounded annular groove is disposed around the bolt body of a retaining body between the protruding ring and the stop ring, a vertical hollow passage and two horizontal through-holes are fabricated in a swivel component, and the lowest end of the slide slot cut contiguously along the bore of the retaining body is of an arcuate shape. As such, after the rounded annular groove and the stop ring of the retaining body are admitted into the hollow passage of the swivel component, two pins are inserted into the through-holes and the rounded annular groove, thereby constrictively conjoining the retaining body and the swivel component to effectively prevent their separation. Additionally, since the lowest end of the slide slot in the retaining body is of an arcuate shape, it is capable of dispersing concentrated stress when pulled by an external force.