The invention relates to a preparation process of continuous fiber reinforced thermoplastic prepreg tape. The preparation process includes: subjecting unidirectional continuous reinforced fibers to fiber splitting processing, and then performing preheating; adopting the melt spinning method to extrude thermoplastic resin into half-melting filaments, and vertically dropping the filaments to the surfaces of preprocessed reinforced fibers; enabling the filaments to array among the reinforced fibers parallelly and evenly through the action of an adhesive roll, enabling the reinforced fibers to be fully infiltrated in thermoplastic resin by means of hot-pressing infiltration, and performing cold-pressing shaping and winding to obtain the continuous fiber reinforced thermoplastic prepreg tape. The prepared prepreg tape is 60-90% in volume content of the reinforced fibers, 10-40% in volume content of the thermoplastic resin, 0.01-0.05mm in thickness, 20-1000mm in width and less than 0.08% in porosity. Production steps of prepreg tape preparation are simplified, infiltration effect of high-viscosity resin is improved, the diameter of the filaments is changed by regulating the takeup speed, resin content of the prepreg tape is controlled effectively, and the continuous fiber reinforced thermoplastic prepreg tape which is uniform in fiber distribution and complete in infiltration is finally obtained.