Aimed at low automation degree of distribution area and in which the operation state cannot be monitored in remote, the smart distribution area based on IDTT-B distribution terminal is designed, which provides scientific and advanced technical means for the operating and management unit to implement meticulous management in distribution area. This paper represents the constructions of smart distribution area, including the upgrading of original distribution area, the construction of new type of smart distribution area based on IDTT-B distribution terminal, communication network, and master station, and especially focus on the development and design of IDTT-B distribution terminal, which is integrated with functions of monitoring, power quality monitoring, temperature and humidity measuring, and low voltage switches communication, thus has high integration, remote control, remote communication and remote software upgrade, and small investment and high cost performance. Finally, the technical features, whole system performance and application of designed smart distribution area based on IDTT-B terminal are introduced. The construction of new type of smart distribution area is of great significance to the construction of a unified strong smart grid in China.