Myxovirus resistance (MX) genes are relevant to a family of interferon (IFN)-stimulated genes. In domestic ruminants such as ewes and cattle, the MX genes have two isoforms called the Myxovirus Resistance 1 (MX1) gene and the Myxovirus Resistance 2 (MX2) gene. INF-tau (INFt) is released from embryonic trophoblast cells in the early days of pregnancy and induces expression of MX genes in the uterine endometrium. In the present study, we summarized the relative expression of the MX1 and MX2 genes during the early days of pregnancy in Kari ewes. Blood samples were taken from inseminated and non-inseminated (control) ewes on different days. Peripheral Blood Monocytes (PBMC) were isolated, and with the addition of MX1 and MX2 gene primers, complementary deoxyribonucleic acid (cDNA) was synthesized by Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). The cDNA was then amplified by rounds of PCR amplification. The amplified product was run on a 2% Agarose gel. The results showed expression of the MX1 and MX2 genes only in pregnant ewes, while no expression was observed in non-pregnant or control ewes. Expression in pregnant ewes was observed on days 14, 16, 17, and 18 after insemination. When comparing the MX1 and MX2 genes, the expression of the MX2 gene was relatively higher than that of the MX1 gene on all experimental days. The result suggested that INF-tau MX genes are expressed during the early days of pregnancy and are involved in the establishment of pregnancy. These results justify the development of this biomarker as a predictive tool for the early detection of pregnancy in ewes and other domestic ruminants.