Segmented telescopes are among the expected future directions of large-diameter telescopes owing to the low difficulty of their processing technology， convenient carrying， and low manufacturing cost. The active support technology provides an important guarantee for the confocal and cophase adjustment of segmented telescopes. This study briefly summarizes the main technologies of the active support system for the main mirror of a segmented telescope and then summarizes and analyzes specific application examples. Finally， it provides design suggestions for the main mirror support system of a segmented telescope. It will provide a valuable reference for the future development of the segmented telescope support technology.