To bring an ashtray to be light, have a simple structure and suppress overflow of cigarette ash and to intend to be easily portable, be produced at a low cost, etc.

In thus portable disposable ashtray, an inner case 3 is constituted of a compounded material made by coating an aluminum foil on the outside surface of a paper board, a stopper piece 31 is formed on a side plate 11 of the inner case 3, an outer case 4 is constituted of a compounded material made by coating an inner face and an outer face of a paper board having a ceramics layer with the aluminum foil and fancy paper, an engaging hole 59 is formed on a side face board 44 of the outer case 4 and an openable cover 62 and a throw opening 63 are formed by notching. The cases are carried by inserting a cigarette container 2 into the inner case 3 and the inner case 3 into the outer case 4. When smoking, the inner case 3 is pulled out together with the cigarette container 2 from the outer case 4 until the stopper piece 31 engages in the engaging hole 59, the openable cover 67 is swinged inside and ash and a cigarette butt 67 are thrown into the outer case from the opened throw opening 63. After the throwing, the inner case 3 is pushed into inside of the outer case 4 together with the cigarette container 2 and the throw opening 63 is closed by the openable cover 62.