The invention discloses a preparation system for carboxylic butadiene-styrene latex. The preparation system comprises an auxiliary reaction kettle, a reaction kettle and a degasification kettle, wherein the auxiliary reaction kettle is connected with a material inlet of the reaction kettle; a material outlet of the reaction kettle is connected with a feeding port of the degasification kettle; the reaction kettle comprises an inner barrel and seal heads packaged at two ends of the inner barrel; a clamp sleeve barrel is arranged outside the inner barrel; and a plurality of ultrasonic treatment devices are distributed on the side wall of the inner barrel. The invention further provides a preparation method for carboxylic butadiene-styrene latex. The preparation system and the preparation method for carboxylic butadiene-styrene latex have the benefits as follows: the reaction efficiency can be effectively improved, the side reaction is reduced, the monomer conversion rate can be increased to higher than 99%, the reaction time can be shortened to 4-7 hours, and the energy consumption is reduced; prepared carboxylic butadiene-styrene latex has excellent tensile strength, abrasion resistance, bonding strength, washing durability, alkali resistance, pollution resistance and the like as well as excellent mechanical stability and chemical stability; and besides, the system has the advantages of simple structure, low failure rate, simplicity and convenience in operation and the like.