Abstract: We took the proper exhausting mining assets in the oil &gas field as object, aims at praxis problems in oil & gas field enterprises actualizing corporation accounting system. According to the requirements of international accounting rules and America No 19 financial accounting rule, the mining assets devaluing
was discussed. We thought that the assets value of oil & gas field enterprises should carry through whole evaluation, and then go along ceiling test. For corporation coming into market, we must throw daylight on its reserves and value information, so that investors can estimate real value of the assets in oil & gas field enterprises.

Key words: mining right, oil-gas reserve, asset devaluing, value evaluation