Abstract: A lamp includes: a base formed with a central hole and having two opposite mounting portions projecting into the central hole; a support seat having a pair of opposite supporting walls that respectively stand upright from the mounting portions of the base, and that cooperatively define an accommodating space which is in spatial communication with the central hole; and a lamp seat adapted to support a lamp member thereon, pivotably mounted on the mounting portions of the base, and including a pair of opposite lamp walls that are disposed between and that are slidably and respectively connected to the supporting walls of the support seat. The lamp seat is rotatable relative to the support seat so as to move in and out of the accommodating space in the support seat.