The invention relates to a low-temperature resistance cotton seed coating agent, which is composed of a bactericide, a plant-growth regulator, a film forming agent, an antifoaming agent and an warning color, and is characterized in that the cotton seed coating agent comprises the following components by mass percentage: 4.0%-4.2% of Seedvax, 4.0%-4.2% of thiram, 0.002%-0.01% of naphthyl acetic acid, 0.002%-0.01% of gibberellin, 0.2%-0.5% of polyvinyl alcohol, 0.3%-0.5% of carboxymethylcellulose sodium, 0.4%-0.5% of antifoaming agent, 1.5%-2.0% of warning color and the balance of water. The low-temperature resistance cotton seed coating agent has the effects of resisting low temperature, preventing disease in seedling stage, promoting the seed germination and rooting and promoting the seedling growth, and also has the advantages of high suspension rate, good film forming ability, even dressing, low shedding rate, low toxicity and convenient usage.