This study compared the efficacy of 70- and 120-w 2-µm thulium:YAG VapoEnucleation of the prostate (ThuVEP) for patients with benign prostatic obstruction (BPO). A prospective analysis of 84 patients with symptomatic BPO and prostatic enlargement (≥60 ml) who underwent either 70-w (n=44) or 120-w ThuVEP (n=40) non-randomly was carried out. Patient demographics and perioperative and 12-month follow-up data were analysed. The mean prostate volume was 79.90±27.49 ml in patients who had received 70-w ThuVEP, which was less than in those who had received 120-w ThuVEP (88.53±25.10; P=0.033). The mean enucleation (resected weight/laser time, 2.16±1.21 g min⁻¹vs. 1.23±0.60 g min⁻¹; P=0.013), operation efficiency (resected weight/total operation time, 0.76±0.35 g min⁻¹vs. 0.42±0.27 g min⁻¹; P=0.000) and percentage of resected tissue (66.93%±22.79% vs. 45.41%±23.33% P=0.000) were higher with 120-w treatment compared to 70-w ThuVEP. One patient (1.2% of total patients) (in the 120-w group) required a blood transfusion postoperatively. Sixty-one patients (73%) were available for review at the 12-month follow-up time point. The quality of life (QoL), International Prostate Symptom Score (IPSS), maximum urinary flow rate (Q_max), postvoiding residual urine (PVR) and prostate volume improved significantly after treatment (P≤0.035) and were not significantly different between those treated with the different devices (70- and 120-w). The median prostate volume reduction was 81.70% and 82.19% with 70- and 120-w ThuVEP, respectively. The incidence of complications was low and did not differ between groups treated with the different devices. Two patients (2.4%) (one per group) had a bladder neck contracture at the follow-up. ThuVEP is a safe and efficacious procedure for the treatment of symptomatic BPO. The incidence of complications was low with both devices. The 120-w thulium:YAG device enhances the effectiveness of ThuVEP with regard to the percentage of resected tissue and the enucleation/operation efficiency.