INTRODUCTION: Tenofovir is a potent nucleotide analogue reverse-transcriptase inhibitor used with other antiretroviral agents for the treatment of human immunodeficiency virus (HIV) infection. Despite the absence of renal toxicity observed in the major clinical trials of tenofovir, several case reports of acute renal failure (ARF) and proximal tubule dysfunction have been described. CASE PRESENTATION: We report a patient who developed ARF and Fanconi syndrome during treatment with tenofovir. Despite severe metabolic acidosis associated with a creatinine of 9.8 mg/dL (866 mumol/L), this patient's condition improved on discontinuation of tenofovir treatment without requiring renal replacement therapy. CONCLUSION: Vigilant screening of kidney function is required regularly after initiation of tenofovir due to possible appearance of renal failure.