Abstract: After using the anode layer ion source for surface activation treatment of glass fiber reinforced cyanate-based composite materials at different distances in the meter range, vacuum coating magnetic arc cathode technology is used to deposit Al coating on the surface of the composite material at the corresponding position. By analyzing the changes in surface energy and surface polarity before and after plasma activation, as well as the surface micro-morphology and film-based bonding strength of the deposited Al coating, the effect of plasma activation technology on the performance of Al coatings deposited on composite materials at different distances in the meter range was evaluated. The results show that the plasma activation treatment can effectively improve the surface energy and surface polarity of the composite, and it increases with the distance. Plasma activation treatment can significantly improve the bonding strength of the metal(Al) coating deposited on the surface of the composite material within a distance of meters. After plasma activation with a discharge voltage of 1000 V, the Al coating in the meter range shows a consistent overall improvement. Compared with the non-activated treatment, the bonding strength is more than doubled. After plasma activation with a discharge voltage of 2000 V, the bonding strength of the Al coating in the meter range increases significantly. Compared with the non-activated, the bonding strength increases by more than 4 times.