Variable intelligent trusses have great advantages in optical equipment and on-orbit assembly. The relevant applications and the development of variable intelligent trusses on large-aperture optical equipment were summarized. Firstly, for serial configuration with less degrees of freedom, the design and application of variable intelligent trusses applied on telescopes were discussed; then, the application of the variable intelligent trusses in the on-orbit assembly, service and adjustment of the telescope were introduced. In view of its high degree of freedom and high positioning accuracy, the feedback methods that could be used in the adjustment of the trusses were summarized, the structure and control algorithm of the trusses were discussed as well. Finally, the technologies currently applied to smart trusses were summarized and the development trend was summarized.