These bacteria are facultative anaerobes, and made up of non-motile and non-sporing cocci (round cells) that are catalase negative.

It is a commensal and commonly inhabits the human mouth, throat, and upper respiratory tract, as part of the oral microbiota.

The family Streptococcaceae is characterized by based upon its 16S rRNA gene sequence analysis within the low (< 50 mol%) G+C branch.

[3] Streptococcus mitis primarily resides in the oral cavity which includes the mouth, nasopharynx, and throat.

Culture plates were made and the identity was later confirmed as Streptococcus mitis at the US Communicable Disease Center at Atlanta, Georgia.