The invention discloses a board quality detection real-time calculation system and method, which belong to the field of hot-rolling quality detection of high-end boards in iron and steel industry, and are particularly used for performing real-time calculation on technological parameter indexes of a quality detection process of the high-end boards. The invention aims to reduce the missing detection rate and increase the product qualification rate. The system comprises a rolling mill data acquisition device, a process database, a business database and an index real-time processing module. The rolling mill data acquisition device stores collected data in the process database; the process database is connected with the index real-time processing module; the business database performs data exchange with the index real-time processing module; the business database stores calculation rule standards and calculation result information; and the index real-time processing module gives out a final detection result. The indexes are calculated in time; the quality detection is comprehensively covered; and standardization rules are adopted.