Abstract: Draping for 2D woven carbon fiber reinforced plastics (CFRPs) influences the quality of final composite parts directly and significantly. The problems of laying reinforced carbon fibers in the manufacturing of 2D woven CFRPs were studied. A material coordinate system, a global coordinate system and a body coordinate system were built. A non-orthogonal constitutive model according to coordinate transformation relation was proposed based on continuum theory. Mechanical properties of 2D woven CFRPs were tested by uni-axial tensile tests for measuring the tensile properties and picture-frame tests for measuring the shear properties. A one-step plies spreading algorithm for 2D woven CFRPs was developed and an independent one-step plies spreading solver was developed. A cover part was spread. The result shows great consistency that the maximum error is only 5.0 mm which is a 1.9% margin of error. The carbon fiber shear angle distributions by calculation are consistent with experimental results and the maximum error is only 4°. The one-step spreading algorithm of 2D woven CFRPs was verified by calculations and experiments.