Abstract: In order to explore the polymorphism of coding sequence（CDS） of Mx1 gene in Tibetan pigs and Yorkshire pigs, twenty healthy adult Yorkshire pigs（over 180 days of age） and 30 healthy adult Tibetan pigs（over 180 days of age） were selected as experimental animals. The CDS of Mx1 gene was amplified by PCR and single nucleotide polymorphisms（SNPs） were analyzed by sequencing.Bioinformatics methods were used to analyze the physicochemical properties, hydrophobicity, phosphorylation site, secondary structure, tertiary structure and interaction with other proteins of the CDS-encoded protein of Mx1 gene, and to analyze the effects of SNPs site on the above indicators of CDS-encoded protein of Mx1 gene. The results showed that four SNPs（C867 G, A923 C, A1241 G and C1324 A） were found in CDS region of Tibetan pig Mx1 gene, and two SNPs（A1241 G and C1324 A） were found in Yorkshire pigs.Among them, C867 G, A923 C and A1 241 G were missense mutations; the corresponding aspartic acid at position 289 becomes glutamic acid; glutamic acid at position 308 becomes alanine; and lysine at position 414 becomes arginine, while C1324 A was synonymous mutation.A total of 663 amino acids were encoded in the CDS of Mx1 gene, and the coding protein was acidic and hydrophilic, with α helix as the main secondary structure. There were 55 phosphorylation sites, including 37 serine（Ser） phosphorylation sites, 13 threonine（Thr） phosphorylation sites, and 5 tyrosine（Tyr） phosphorylation sites. The Mx1 gene encodes proteins with interfer on stimulated exonuclease gene15（ISG15）, ubiquitin specific peptidase 18（USP18）, DDX-box helicase58（DDX58）, eukaryotic translation initiation factor 2 alpha kinase 2（EIF2 AK2）, myxovirus resistance dynamin like GTPase 2（Mx2）, structural domain containing protein 5（HECT and RLD domain containing E3 ubiquitin protein ligase 5, HERC5）, 2′,5′-oligoadenylate synthetase 1（OAS1）, Janus kinase 1（ JAK1）, cub2 structural domain protein（IRG6）, and OAS-like protein（OASL） are in reciprocal relationship.In addition, the changes of amino acids caused by SNPs in CDS of Mx1 gene only affected the secondary structure, hydrophobicity and phosphorylation sites of the protein, they but did not change the properties of the tertiary structure. The results indicated that Mx1 protein still played its original function.