Streptococcus constellatus is a member of Streptococcus anginosus group (SAG) that tends to cause pyogenic infections in various cavities. However, Streptococcus constellatus is not easily detected as a pathogen in the routine laboratory tests. As a member of SAG, it is the rarest to cause severe infections, which lead to ICU hospitalization. This case report adds valuable information to the current body of knowledge of these infective diseases.