A measure according temperature estimation of a heated armor plate′s original surface based on deferred infrared temperature-measuring was given with the infrared testing the temperature technology combined the conduction with convection.By the numerical value calculated validated,this method is able to give a highly precisely examination result,at the meantime this article with the simple software worked out according to this method have the ability to compute the temperature of armor plate,conveniently and immediately as well as to realize the visual operation to direct the practice of steel production.