Abstract: A full-order global analysis is made to class 1 polymolecular reaction system. Firstly, the non-existence of a closed orbit is decided on by means of finding the boundary lines of the system. Secondly, although lots of qualitative analysis has been made about finite and infinite singular point, a still more accurate discussion is done and brings about a conclusion that one of the singular point cannot but be a crunode; also proved is that, of the infinite singular points, the strike direction of the orbit in the first quadrant is irrelevant to the value of p andq. Lastly, based on the above discussion, the global phase map is put forth for the said system.