Abstract: Digital twins establish numerical models based on physical objects, and use technologies such as artificial intelligence, machine vision and augmented reality to achieve performance optimization and predictive analysis of the system. Based on the history of evolution, the concept and implementation of digital twins are analyzed; By summarizing two multi-modal perception technologies of image monitoring and sound monitoring and precision feeding control technology, the precision pig farming is analyzed; the application of digital twins in modern pig farm energy consumption analysis, three-dimensional The application of visualization, predictive model, and environmental simulation; based on the three perspectives of physical model cost, pig raising database, and development resources, the limitations are analyzed; for the maturity of technology, the analysis is extended with application cases in other fields; finally, the modern pig farm is pointed out the development trend of digital twin technology in production provides a reference for the construction of smart pig farms.