Abstract: This study aims at screening the early pregnancy diagnosis marker of dairy cows and improving the economic benefits of dairy farming. Ten Holstein cows were selected from some cattle farms in Beijing. Blood was taken on the 1st, 4th, 7th, 10th, 13th, 16th, and 19th day after insemination, the expression trends and changes of Wnt7a and PR were analyzed by fluorescence quantitative PCR and western blotting. The pregnancy test of 10 Holstein cows was conducted with the direct inspection, 7 of them were conceived and 3 were unpregnancy. By detecting the expression levels of Wnt7a and PR genes in the blood of pregnant and non-pregnant cows, it was found that the expression level of Wnt7a gene in the blood of pregnant cows was higher than that of nonpregnant cows. In particular, the expression level of Wnt7a gene in pregnant cows increased significantly on the 7th day after insemination, the level expression of Wnt7a protein showed the similar trend. The PR gene showed a decreased-expression trend on the 1st day after insemination in all 10 cows and it maintained a very low expression state. Wnt7a has the potential as a diagnostic marker for early pregnancy in dairy cows, which has the advantage of advancing the detection window to the 7th day after insemination; PR does not have the advantage as a marker factor. By exploring the changes of the relative factors affecting early pregnancy, it can provide a theoretical basis for the time window of pregnancy test advancing to the early pregnancy stage.