This paper represents in detail various conditions for determing boric oxide in leaching solution of optical glasses by the spectrophotometric method. An expedite spectrophotometric method developed in the institute is introduced. The experimental programme of this method is different from that of the International Commission on Glass(ICG). The technics and the accuracy of the measurement obtained are better thom the method of ICG. This mothod can provide important data for the investigation and the measurement of physical chemistry properties of glass surface.