A furniture assembly includes a first furniture piece, a second furniture piece, and a safety device. The second furniture piece is movable with respect to the first furniture piece. The safety device includes a first fitting and a second fitting. One of the first fitting and the second fitting is detachably coupled to one of the first furniture piece and the second furniture piece, and the other one of the first fitting and the second fitting is located in the other one of the first furniture piece and the second furniture piece. When the second fitting is at the stop position, the second fitting blocks the first fitting, thereby stopping the second furniture piece from moving in a direction with respect to the first furniture piece.