Guangdong green jade, also known as Guangdong green or Xinnan jade, is produced in Guangning County of western Guangdong Province. It belongs to altered sericite jade and has abundant colors, such as green, white, yellow and black, with green being the main color. Guangdong green jade is an important kind of special jade material in southern China. However, studies of Guangdong green jade are relatively insufficient, and there are divergences on some problems, which severely restrict the scientific understanding of jade and jade development and utilization. With Guangdong green jade as the study object and by means of field investigations and modern testing methods such as petrographical observation, mineral chemical analysis and XRD, the authors made a systematic and detailed study concerning its mineral composition, chemical composition, petrological features, with the purpose of explaining coloring mechanism of Guangdong green jade.