The invention aims at providing an automobile start supply voltage detection alligator clip with a pull-off function, including: a positive alligator clip structure; a negative alligator clip structure; a male contact head; and a positive pull-off end and negative pull-off end arranged on the male contact head; the positive/negative alligator clip structure includes a positive/negative upper cover, positive/negative upper cover contact piece, positive/negative pull-off contact piece, positive/negative pull-off spring, positive/negative lower cover contact piece, positive/negative lower cover, and positive/negative upper and lower covers pressure spring; an internal positive/negative silica gel wire is sleeved in an external positive/negative silica gel wire by an internal silica gel wire sleeving process; and the positive/negative pull-off contact piece is connected to a positive/negative pull-off detection end by the internal positive/negative silica gel wire. The male contact head, positive pull-off detection end and negative pull-off detection end are wrapped together by encapsulation.