Abstract: An apparatus for extinguishing a lighted cigarette comprises a hollow external seat and a storing container. A blade for cutting and extinguishing the burning portion of a lighted cigarette in combination with an L-shaped plate are provided within a seat. Both the plates are made from shape memory alloys having different temperature reaction gradients. When the burning portion of a cigarette is placed into the seat and comes into contact with the blade, the plate will restore to its memory shape by the temperature response in cutting off the lighted portion of the cigarette and extinguishing the lighted portion by pressing it on the L-shaped plate. The L-shaped plate stretches straight to let the cigarette ash drop into the storing container. When the temperature of the L-shaped plate is decreased, the plate recovers to its original position to cover the storing container. The cigarette ash is thus restricted within the storing container to prevent it from dispersing and causing pollution.