The invention discloses a seed dressing agent for garlic. The seed dressing agent comprises the following components, in parts by weight: 8-14 parts of prochloraz or tebuconazole carbendazim, 0.7-1.5parts of Zhongshengmycin, 3-9 parts of hymexazol, 10-20 parts of fludioxonil metalaxyl-M, 5-8 parts of avermectin or 10-30 parts of bifenthrin, and 8-33 parts of Atailing or 1-3 parts of vitacat or amixture of Atailing and vitacat. The seed dressing agent provided by the invention can kill main pests and diseases on garlic seeds, control the pests and the diseases of the garlic from a source, andcan promote rooting, the roots are strong, the seedlings are regular, and an occurrence of the pests and the diseases in the late stage can be reduced.