A terminal cover includes a lid and a cover body. The lid is rotatable around a hinge to open or close the cover body. An assembly of the cover body and the lid closed has a first side wall and a second side wall. A shoulder side wall that is at least one of the first and second side walls has a shoulder. The shoulder side wall is equipped with a first snap-fit and a second snap-fit. The first snap-fit is located closer to the hinge than the shoulder is, while the second snap-fit is located farther away from the hinge than the shoulder is. If the second snap-fit is undesirably unlocked, the shoulder serves to block transmission of resultant deflection of a portion of the shoulder side wall to the first snap-fit, thereby eliminating a risk that the first snap-fit may be accidently undone by the undesirable unlocking of the second snap-fit.