Abstract: his paper introduced a lightweight Dual-axis solar array drive assembly (SADA), aiming at two key technologies of lightweight and long life. The Dual-axis SADA consists of A-axis which provides 360º of rotation and power transfer through the use of a slip ring device and B-axis which provides ±90º of travel and incorporates a simple flex loop for power transfer. The accelerated life test of key moving parts of SADA including the slip ring and the harmonic reducer were preformed and passed. The designed principle prototype of SADA has some merits, such as compact structure, good stiffness and light weight. The thermal analysis of the Dual-axis SADA had been preformed. The measures of thermal control are presented by comparing temperature distribution under different schemes.