Objectives The feeding mode of whole-plant corn silage was studied to provide practical guidance for the improvement of fattening techniques for white yaks and the sustainable development of agriculture and animal husbandry in Yongdeng County. Methods 2 groups of white yaks were selected to simulate the typical farming scale of local farmers. 15 yaks aged 1.5 years old with an average body weight of about 400 kg at the beginning of the experiment were in each group. The whole plant-corn silage was used as the main feed in the experimental group, while the traditional forage was used in the control group. The growth of body mass, the conversion rate of feed, and health indexes in the two groups of cattle were recorded. Results The feeding mode of using whole-plant corn silage significantly improved the utilization efficiency of feed and the weight gain efficiency of beef cattle. Compared to traditional feeding modes, the weight gain increased by 15% to 20%, the cost of daily feed decreased by 5% to 8%, and the potential income increased monthly by 12% to 20%. The cattle in the experimental group had better health conditions. Conclusions Taking the whole plant corn silage feeding model as the core, Optimizing the fattening techniques for white yaks with the whole-plant corn silage feeding mode as the core in Yongdeng County can reduce the cost of farming and promote the transformation of local animal husbandry towards modernization with high efficiency.