Objectives The infection status and epidemic trend of brucellosis in cattle and sheep in Anding District, Gansu Province was studied and the causes and transmission routes of the epidemic were analyzed to provide scientific basis for formulating specific measures for prevention and control. Methods The cattle and sheep having not been vaccinated against brucellosis from large-scale cattle and sheep farms and free-range households in Anding District, Gansu Province in 2023 were randomly selected. A total of 21010 serum samples including 13284 sheep serum samples and 7726 cattle serum samples were collected from January to December 2023. The epidemiology of brucellosis in cattle and sheep in Anding District was analyzed. The suspected cases were confirmed by laboratory testing. Results Among different farming sites, the positive detection rate in breeding farms was the lowest, with a total positive detection rate of 0.11% in sheep breeding farms and 0 in cattle breeding farms. During the period of one-year monitoring, the positive detection rate of brucellosis in sheep was relatively higher in March, September, and October, with rate of 0.37%, 0.36%, and 0.27%, respectively. The positive detection rate of brucellosis in cattle was relatively higher in April, August and September, with rate of 0.28%, 0.32% and 0.31%, respectively. Conclusions It is indicated that the brucellosis in cattle and sheep is more prevalent in the spring and autumn seasons. Therefore, the effective measures for prevention and control should be taken from aspects including monitoring and purification, disinfection and farming management to reduce the harm caused by brucellosis in cattle and sheep.