The invention belongs to the field of materials and specifically relates to a preparation method of pre-dispersed carbon nano-tube rubber masterbatches. The method is characterized in that the rubber masterbatches comprise the following ingredients, by weight, 5-100 parts of carbon nano-tube, 5-100 parts of rubber, 5-100 parts of wax, 0.5-50 parts of a dispersing aid, 0.5-5 parts of an anti-aging agent and 0.1-10 parts of an activator. The preparation method of the rubber masterbatches comprises the following specific steps: carrying out high-speed shearing on the above ingredients, mixing, carrying out in situ activated modification on carbon nano-tube such that carbon nano-tube is uniformly dispersed and has no micron-scale aggregate, and pelleting so as to obtain the pre-dispersed high-concentration carbon nano-tube rubber masterbatches. By the use of the pre-dispersed carbon nano-tube rubber masterbatches prepared by the above formula and method, tear strength of tire tread rubber can be raised by about 5-10% and even more, wear volume of Akron is reduced by about 30% and even more, volume resistivity is minimized by two orders of magnitudes, and mechanical properties such as tensile strength, elongation at break and the like are basically unchanged or increased a little.