The results indicated that, with the replication of the MDV RB1B strain, the expression level of Wnt/β-catenin signaling pathway-related genes β-catenin, TCF4, LEF1, c-Myc, and Cyclin D1 were significantly downregulated after 24 h of RB1B strain infection and significantly upregulated at 60 h. The gene discussed is LEF1; the disease is infection.