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Previous studies on the prevalence and transmission mechanism of oxazolidinone resistance gene <i>poxtA</i> in CoNS are lacking, which this study addresses. By screening 763 CoNS isolates from different sources of several livestock farms in Guangdong, China, 2018–2020, we identified that the <i>poxtA</i> was present in seven CoNS isolates of pig and feed origins. Species identification and multilocus sequence typing (MLST) confirmed that seven <i>poxtA</i>-positive CoNS isolates were composed of five ST64-<i>Staphylococcus haemolyticus</i> and two <i>Staphylococcus saprophyticus</i> isolates. All <i>poxtA</i>-positive <i>Staphylococcus haemolyticus</i> isolates shared similar pulsed-field gel electrophoresis (PFGE) patterns. Transformation assays demonstrated all <i>poxtA</i>-positive isolates were able to transfer <i>poxtA</i> gene to <i>Staphylococcus aureus</i> RN4220. S1-PFGE and whole-genome sequencing (WGS) revealed the presence of <i>poxtA</i>-carrying plasmids in size around 54.7 kb. The plasmid pY80 was 55,758 bp in size and harbored the heavy metal resistance gene <i>czcD</i> and antimicrobial resistance genes, <i>poxtA</i>, <i>aadD</i>, <i>fexB</i> and <i>tet</i>(L). The regions (IS<i>1216E</i>-<i>poxtA</i>-IS<i>1216E</i>) in plasmid pY80 were identified in <i>Staphylococcus</i> spp. and <i>Enterococcus</i> spp. with different genetic and source backgrounds. In conclusion, this was the first report about the <i>poxtA</i> gene in <i>Staphylococcus haemolyticus</i> and <i>Staphylococcus saprophyticus</i>, and IS<i>1216</i> may play an important role in the dissemination of <i>poxtA</i> among different Gram-positive bacteria.