Abstract: A glass-fiber reinforced plastic pipe comprises a pipe body and an inner core fixedly provided on an inner wall of the pipe body, wherein an upper end of the inner core is lower than an upper end of the pipe body, so that a first heat-insulating space is formed between the upper ends of the inner core and the pipe body, and a lower end of the inner core is higher than a lower end of the pipe body, so that a second heat-insulating space is formed between the lower ends of the inner core and the pipe body. Due to the inner core as a reinforce structure, the shear resistance strength of the glass-fiber reinforced plastic pipe is improved without increasing the thickness of the pipe wall, and furthermore the mechanical performance of a supporting device of the cryogenic pressure vessel is improved.