Staphylococcus warneri is a member of the bacterial genus Staphylococcus, consisting of Gram-positive bacteria with spherical cells appearing in clusters. It is catalase-positive, oxidase-negative, and coagulase-negative, and is a common commensal organism found as part of the skin flora on humans and animals. Like other coagulase-negative staphylococci, S. warneri rarely causes disease, but may occasionally cause infection in patients whose immune system is compromised.