Streptococcus constellatus (S. constellatus) is a well-known part of the normal flora in humans. Pyogenic spondylitis (PS) induced by S. constellatus is very rare. In this case, a 46-year-old male patient presented to our hospital with a 2-month history of low back pain and weakness in both legs. Based on his clinical manifestations, laboratory findings, blood culture results, imaging and histopathological findings, the patient was diagnosed with PS caused by S. constellatus. One unique aspect of this case is the acute and severe course of infection, which resulted in multiple organ dysfunction syndrome and septic shock in the first week and rapid vertebral destruction within 2 months of the patient's admission. His obese status may be relevant to his presentation. This case report suggests that S. constellatus infections should not be overlooked, especially in patients with known risk factors and predispositions to infectious diseases.