Signal transducer and activator of transcription 1 (STAT1) is a critical component of the transcription factor complex in the interferon (IFN) signaling pathways. Of the seven STAT isoforms, STAT1 is a key mediator of type I and type III IFN signaling, but limited information is available for the STAT genes in the water buffalo. Here, we amplified and identified the complete coding sequence (CDS) of the buffalo STAT1 gene by using reverse transcription polymerase chain reaction (RT-PCR). Sequence analysis indicated that the buffalo STAT1 gene length size was 3437 bp, containing an open reading frame (ORF) of 2244 bp that encoded 747 amino acids for the first time. The buffalo STAT1 CDS showed 99, 98, 89, 93, 86, 85, and 87% identity with that of Bos taurus, Ovis aries, Homo sapiens, Sus scrofa, Rattus norvegicus, Mus musculus, and Capra hircus. The phylogenetic analyses revealed that the nearest relationship existed between the water buffalo and B. taurus. The STAT1 gene was ubiquitously expressed in 11 buffalo tissues by real-time PCR, whereas STAT1 was expressed at higher levels in the lymph. The STAT1 gene contained five targeted microRNA sequences compared with the B. taurus by the miRBase software that provide a fundamental for identifying the STAT1 gene function.