BACKGROUND: New, minimally invasive surgeries have emerged as alternatives to transurethral resection of the prostate (TURP) for the management of lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH). Aquablation is a novel, minimally invasive, water-based therapy, combining image guidance and robotics for the removal of prostatic tissue. OBJECTIVES: To assess the effects of Aquablation for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia. SEARCH METHODS: We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Web of Science, and LILACS), trials registries, other sources of grey literature, and conference proceedings published up to 11 February 2019, with no restrictions on the language or status of publication. SELECTION CRITERIA: We included parallel-group randomised controlled trials (RCTs) and cluster-RCTs, as well as non-randomised observational prospective studies with concurrent comparison groups in which participants with BPH who underwent Aquablation. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion at each stage, and undertook data extraction and 'Risk of bias' and GRADE assessments of the certainty of the evidence. We considered review outcomes measured up to and including 12 months after randomisation as short-term and beyond 12 months as long-term. MAIN RESULTS: We included one RCT with 184 participants comparing Aquablation to TURP. The mean age and International Prostate Symptom Score were 65.9 years and 22.6, respectively. The mean prostate volume was 53.2 mL. We only found short-term data for all outcomes based on a single randomised trial.Primary outcomesUp to 12 months, Aquablation likely results in a similar improvement in urologic symptom scores to TURP (mean difference (MD) -0.06, 95% confidence interval (CI) -2.51 to 2.39; participants = 174; moderate-certainty evidence). We downgraded the evidence certainty by one level due to study limitations. Aquablation may also result in similar quality of life when compared to TURP (MD 0.27, 95% CI -0.24 to 0.78; participants = 174, low-certainty evidence). We downgraded the evidence certainty by two levels due to study limitations and imprecision. Aquablation may result in little to no difference in major adverse events (risk ratio (RR) 0.84, 95% CI 0.31 to 2.26; participants = 181, very low-certainty evidence) but we are very uncertain of this finding. This would correspond to 15 fewer major adverse events per 1000 participants (95% CI 64 fewer to 116 more). We downgraded the evidence certainty by one level for study limitations and two levels for imprecision.Secondary outcomesUp to 12 months, Aquablation may result in little to no difference in retreatments (RR 1.68, 95% CI 0.18 to 15.83; participants = 181, very low-certainty evidence) but we are very uncertain of this finding. This would correspond to 10 more retreatments per 1000 participants (95% CI 13 fewer to 228 more). We downgraded the evidence certainty by one level due to study limitations and two levels for imprecision.Aquablation may result in little to no difference in erectile function as measured by International Index of Erectile Function questionnaire Erectile Function domain compared to TURP (MD 2.31, 95% CI -0.63 to 5.25; participants = 64, very low-certainty evidence), and may cause slightly less ejaculatory dysfunction than TURP, as measured by Male Sexual Health Questionnaire for Ejaculatory Dysfunction (MD 2.57, 95% CI 0.60 to 4.53; participants = 121, very low-certainty evidence). However, we are very uncertain of both findings. We downgraded the evidence certainty by two levels due to study limitations and one level for imprecision for both outcomes.We did not find other prospective, comparative studies comparing Aquablation to TURP or other procedures such as laser ablation, enucleation, or other minimally invasive therapies. AUTHORS' CONCLUSIONS: Based on short-term (up to 12 months) follow-up, the effect of Aquablation on urological symptoms is probably similar to that of TURP (moderate-certainty evidence). The effect on quality of life may also be similar (low-certainty evidence). We are very uncertain whether patients undergoing Aquablation are at higher or lower risk for major adverse events (very low-certainty evidence). We are very uncertain whether Aquablation may result in little to no difference in erectile function but offer a small improvement in preservation of ejaculatory function (both very low-certainty evidence). These conclusions are based on a single study of men with a prostate volume up to 80 mL in size. Longer-term data and comparisons with other modalities appear critical to a more thorough assessment of the role of Aquablation for the treatment of LUTS in men with BPH.