Although other hantaviruses are associated with renal manifestations, hantavirus cardiopulmonary syndrome (HCPS) has not been associated with such sequelae. The HCPS survivors were prospectively evaluated for renal complications. Subjects underwent yearly evaluation, laboratory studies, and 24-hour urine collection. Thirty subjects were evaluated after recovery from HCPS with the first follow-up at a median of 7.4 months after discharge. Subjects were a wide age range (18-51) but had an equal gender composition. Eighteen of 30 (60%) returned for > 1 evaluation. Half (15/30) had a 24-hour urine collection with > 150 mg of total protein and 6 had > 300 mg. Seven had a Cockcroft-Gault creatinine clearance (CrClCG) < 90 mL/min/1.73 m2 and 2 were < 60. Fifty-three percent met the definition of chronic kidney disease. Those treated with extracorporeal membrane oxygenation had less renal sequelae (P = 0.035). Our data suggest that renal sequelae may occur in HCPS. Further study of renal complications of New World hantavirus infections are needed.