To observe the influences of erectile dysfunction (ED) by age, prostate size and lower urinary tract symptom (LUTS) undergoing two micro (thulium) laser resection of prostate-tangerine technique (TmLRP-TT). A total of 50 BPH (benign prostatic hyperplasia) patients underwent TmLRP-TT with a 70 W laser power. The patient prostate volume, international prostatic symptomatic score (IPSS), maximal flow rate and international index of erectile function (IIEF-5) were assessed preoperatively. A retrospective assessment was made after surgery and at a 6-month follow-up. They were divided into 2 groups according to prostate volume ≤ 50 or > 50 ml, age ≤ 65 yrs or > 65 yrs, IIEF-5 ≤ 20 or > 21 and IPSS ≤ 27 or > 27 respectively. The postoperative influences of erection by age, prostate size and LUTS were observed. Significant differences existed between pre-operation and 6 months post-operation in terms of IPSS (25.35 ± 5.6 vs 9.52 ± 3.1, P < 0.01) and maximal flow rate (6.51 ± 1.21 vs 13.4 ± 2.7 ml/s, P < 0.01). There was no difference between pre-operation and 6 months post-operation (34 vs 32 cases, χ(2) = 0.673, P = 0.603). The patients with prostate volume >50 ml group had 9 additional ED cases while those with IPSS >27 group contained 11 fewer ED cases. There were significant differences between both groups (χ(2) = 5.255, P = 0.002; χ(2) = 11.560, P = 0.001 respectively). BPH patients aged over 65 years old were more likely to suffer ED than those under 65 years old (χ(2) = 5.882, P = 0.015). However, there was no significant difference in age in terms of suffering postoperative ED (χ(2) = 3.125, P = 0.077). TmLRP-TT can significantly improve LUTS in BPH patients. The presence of large volume prostate is an independent risk factor for an increased number of ED patients after TmLRP-TT. LUTS is an independent risk factor for ED. And TmLRP-TT may improve the ED patients with severe LUTS.