Abstract: The group Ⅲ-nitride materials are ideal for high power and high temperature devices due to their large energy band-gap, high breakdown voltage, high peak electron velocity and high electron sheet density in channels when used in a heterostructure. Major developments in wide gap Ⅲ-Ⅴ nitride semiconductors have recently led to the commercial production of high-power UV/Blue/Green light-emitting diodes and to the demonstration of room-temperature violet laser light emission in InGaAs/GaN/AlGaAs-based heterostructures under pulsed and continues-wave operations. The group Ⅲ-nitride materials are also ideal for photoelectric devices. These results and discussion are described in this paper.