Abstract: In order to meet the requirements of high precision, lightweight and low cost of the SKA (Square Kilometer Array) reflector, the triangular aluminum alloy panel unit with adhesively stiffened panel structure is developed. Firstly, the structure layout of the back rib is designed, the efficient layout is selected by simulating the structure deformation. Secondly, through the parameter design of the back rib and skin, the dimension of the panel structure is optimized. Finally, the triangular panel unit is trial-manufactured by vacuum negative pressure bonding process. The results show that the structure design and the manufacturing method of triangular panel unit are innovative and can meet the requirements of the SKA radio telescope.