The invention relates to a construction process of a wind power tower tube. The construction process comprises the procedures of sectioned tube section manufacturing, tower tube flange installation, and tower tube assembly; sectioned tube section manufacturing comprises the procedures of factory inspection of raw materials, material reinspection, pretreatment of a steel plate, numerical control cutting blanking, dimensional inspection, groove machining, circle rolling, group-welding of longitudinal joints, circle rectifying, measuring of tube section ovality, 100%UT detection and T-shaped seam100%MT detection; tower tube flange installation is achieved through the procedures of flange detection, tower tube detection, flange fixing, tube body installation, welding measuring, bottom flangeassembly, tube body connection, bolt connection, tube body positioning welding and detection after welding jointly; and tower tube assembly comprises the procedures of grouping of tube sections and flange nipples, inspection, welding, 100% UT detection, inspection, drawing of position lines of inner parts, inspection, group-welding of the inner parts, anticorrosion treatment, assembly of the innerparts, packing and forwarding. The construction process has the advantage of being high in precision.