The role of the basic factors in the wet fiber winding process was investigated from the point of view of the actual wet-wound parameters and the property of composite material. In the present work, a PBO fiber-reinforced epoxy-matrix composite material was prepared by a wet fiber-winding process. The effects of processing factors such as the volume fraction of PBO fiber, the preheating temperature of mandrel, the infiltration temperature and time of epoxy resin, and winding tension, on the tensile strength and interlaminar shear strength (ILSS) of the unidirectional composite materials were investigated. To evaluate correctly how the above-mentioned parameters affect the mechanical performances of the composite materials, a pair of standardized pressure vessels with a diameter of 150 mm were fabricated via the winding method. The optimum conditions are obtained as follows: the preheating temperature of mandrel is 60-70 °C, winding tension is 30-40 N, and the penetration temperature and time of epoxy resin into PBO fiber are 45 °C and 1-2 s, respectively. Under the conditions, the ILSS and tensile strength of the composite materials are 30 MPa and 2980 MPa, respectively. The burst pressure and performance factor of the manufactured pressure vessels is as high as 34 MPa and 60.4 km, respectively. It is demonstrated that high quality rings and vessels can be efficiently manufactured by methods described in the paper.