This paper presents the development of gateway for smart grid for the interoperable communication between IEC 61850 station leveled devices and one of legacy Modbus, DNP3, and IEC60870-5-101/104/103 communication protocol devices of bay level in substation or for the exchange of information between IEC 61850 substation and SCADA control center. The data-mapping model is designed for the exchange of information and the gateway configuration tool is developed for generating meta-data based on XML Schema. this paper is mostly concerned with the design and realization of gateway system for the interoperable data communication between a legacy protocol device and IEC61850 based devices or systems.