The invention relates to the technical field of fracturing of horizontal well groups in oil fields, in particular to a method for synthesizing an efficient slick water drag reducer with low molecular weight. The method comprises the steps as follows: firstly, after the inside of a reaction kettle is cleaned, deionized water is poured in based on the total production quantity, acrylamide, acrylic acid, sodium hydroxide and sodium vinylsulfonate are sequentially poured into the reaction kettle, another material is added after one material is thoroughly dissolved, the solution in the reaction kettle is evenly mixed, and the total solution mass in the reaction kettle at this moment is A. The method achieves the beneficial effects that the slick water drag reducer easily dissolves in water, the resistance reduction effect is good, the friction effect on flow of a liquid pipe is obviously reduced, an oil and gas production channel is not blocked, no damage is caused to reservoirs after fracturing, and salt resistant and shearing resistant capacities are high; the slick water drag reducer is easily prepared, environment-friendly and recyclable, thereby having low use cost and good universality, and being particularly applicable to fracturing construction development for resources such as shale oil and gas reservoirs, compact sandstone oil and gas reservoirs and the like, which have large potential reserves.