Abstract: The Nobel Prize in Physics 2014 rewarded to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura as they have invented the blue light-emitting diode (LED). It is a new energy-efficient and environment-friendly light source. The Laureates’ research works and achievements are introduced briefly in this article . The physical principle and structure of the blue light-emitting diode are described sketchily.