Background: Nontraumatic spontaneous renal hemorrhage is caused by tumor such as renal cell carcinoma or angiomyolipoma in most cases. Vasculitis including periarteritis nodosa or antineutrophil cytoplasmic antibody (ANCA)-mediated vasculitis may also be the next underlying background. Herein, we report the first case of nontraumatic spontaneous bilateral renal hemorrhage combined with chronic infection of Chlamydia pneumoniae.Case presentation: The patient serially suffered from left and right back pain within 78 days due to bilateral spontaneous renal hemorrhages. Transcatheter arterial embolization was successfully performed twice to treat serial spontaneous bilateral renal hemorrhages. The serological examination apparently revealed his chronic infection of Chlamydia pneumoniae and a slight elevation of anti-deoxy nucleotide antibodies. Furthermore, computed tomography (CT) angiogram and 67galium citrate scintigram also suggested underlining severe arteriosclerosis without severe inflammation in bilateral kidneys. Chronic infection of Chlamydia pneumoniae and underlying autoimmune vasculitis may pull a trigger of bilateral spontaneous renal hemorrhages although the real mechanisms remain unknown. Conclusions: In conclusion, we reported an extremely rare case of nontraumatic spontaneous bilateral renal hemorrhage of unknown etiology. Severe atherosclerosis caused by chronic infection due to Chlamydia pneumoniae may predispose to the vascular vulnerability of the bilateral renal arteries in close association with hypertension, oral intake of antiplatelets, and underlying autoimmune vasculitis.