To study the human-robot collaborative assembly process of space erectable truss structure, an innovative configuration that suitable for radial fast assembly of truss modules was proposed in this work. Based on state matrix and adjacency matrix, mathematic models of assembly sequence, assembly mode and assembly process of truss structures was established firstly. Then, the human-robot capability constraints of truss assembly in space environment were analyzed. The hierarchical decomposition of assembly tasks based on dynamic operation element analysis was proposed. The process and assignment scheme of human-robot collaborative assembly tasks suitable for programming were given by using the principle of comparison and allocation. Finally, to verify the rationality and feasibility of the proposed assembly process, a ground demonstration test was carried out for the collaborative assembly of 5 m long erectable truss structure by human wearing simulated space suit and manipulator. The results showed that, the proposed scheme can provide an effective way to realize the on-orbit construction of large space facilities.