A decorative lamp includes a flexible mounting shell with a first end, a second end opposite the first end, a through hole extending through the first and second ends, a ridge extending into the through hole, and a first plurality of grooves. A light emitting body is positioned at least partially within the mounting shell, and the light emitting body extends through the second end of the mounting shell. A tail plug is positioned at least partially within the mounting shell adjacent the first end, and the tail plug includes a second plurality of grooves. The first plurality of grooves and the second plurality of grooves are aligned to form tracks configured to receive wires coupled to the light emitting body, and an outer surface of the mounting shell includes a stepped structure.