IEC61850-9-1/2 defined the sampling value transmission which is an important model in the IEC61850 standards. In-depth understanding of 9-1 and 9-2 agreement has great significance to develop substation automation system that meets the IEC61850 standards. This paper introduces the content and the implementation methods of the 9-1 and 9-2 agreement in detail. The analysis and comparison are made to 9-1 and 9-2 from the sampling value transmission content, the communication methods, the network forms, the SCSM mapping way and so on. The applications of the two protocols in the actual project are compared and point of view is put forward. It is significant to learn and master the IEC61850 standards and the IED equipment process bus’s communicating design.