Autosomal dominant polycystic kidney disease (ADPKD) remains a significant cause of end stage renal disease. Unlike other nephropathies, the role of angiotensin-converting enzyme inhibitors (ACEi) is not as established in ameliorating the rate of decline of renal function in this disorder. We conducted a systematic review of the literature to investigate if ACEi can slow the progression to renal failure. Three were enalapril comparative trials: two trials compared enalapril against a calcium channel blocker and the other against a beta blocker. Study quality was evaluated using standardized criteria. Data was collected with regards benefits and harms of theraphy, particularly annual rate of decline of renal function and its percentage against baseline. After mata-analysis, there was a greater percentage decline in creatinine clearance per year for groups treated with ACEi. This was significant for the fixed effects model but not for the random effects model. Reviewers conclude that treatment with ACEi may not be the best option for ADPKD patients with hypertension and close monitoring is recommended.