In the aviation industry, the novel reconfigurable jig has a good application prospect. However, compared with traditional fixed jigs, the flexible structure of reconfigurable jig increases the assembly difficulty, as well as the disadvantage of cooperation between devices. To cope with these problems, we propose a reconfigurable jig assistant assembly (RJAA) system based on wearable devices in this paper, which can enhance the collaboration between humans and machines, and improve the automation level of assembly operations. Firstly, the architecture of the RJAA system is presented, which is composed of three units, i.e. server application unit, wearable application unit, and assembly execution/auxiliary unit. Secondly, in order to achieve the collaboration within the RJAA system, a unified message cooperation communication protocol is designed. Finally, we tested the developed system on the assembly of a 6-UPS parallel mechanism to validate the effectiveness and feasibility of the proposed system.