The present invention provides a method, an apparatus, a computer system and a readable storage medium for determining the emission of carbon dioxide produced in a magnesite processing process, the method performed by a terminal device, comprises the steps of: receiving activity level data sent by a processing device, wherein the activity level data is the industrial product yield obtained based on magnesite processing in a preset time period; obtaining an emission factor of carbon dioxide, wherein the emission factor is a carbon dioxide emission factor determined based on an industrial process of magnesite processing in a preset time period; and according to the activity level data and the emission factor, determining the carbon dioxide emission amount of the magnesite processing-based industrial process in a preset time period. The problem that greenhouse gas emission accounting generated in the existing industrial process is not comprehensive is solved, a greenhouse gas statisticalaccounting system is perfected, the emission amount of carbon dioxide generated by magnesite processing is automatically calculated, and the method is accurate and efficient.