Studies reported that Serenoa repens was effective in relieving lower urinary tract symptoms (LUTS). This article carried out a systematic review and meta-analysis to compare Serenoa repens with tamsulosin in the treatment of benign prostatic hyperplasia (BPH) after at least 6-month treatment cycle. Four studies involving 1,080 patients (543 in the Serenoa repens group and 537 in the tamsulosin group) were included in the meta-analysis. The results were as follows: compared with tamsulosin, Serenoa repens had a same effect in treating BPH in terms of International Prostate Symptom Score (IPSS) (mean difference [MD] 0.63, 95% confidence interval [CI] [−0.33, 1.59], p = 0.20), quality of life (QoL) (MD 1.51, 95% CI [−1.51, 4.52], p = 0.33), maximum flow rate (Qmax) (MD 0.27, 95% CI [−0.15, 0.68], p = 0.21), postvoid residual volume (PVR) (MD −4.23, 95% CI [−22.97, 14.44], p = 0.65), prostate-specific antigen (PSA) (MD 0.46, 95% CI [−0.06, 0.97], p = 0.08) with the exception of prostate volume (PV) (MD −0.29, 95% CI [−0.41, −0.17], p < 0.00001). For side effects, Serenoa repens was well tolerated compared with tamsulosin especially in ejaculation disorders (odds ratio [OR] = 12.56, 95% CI [3.83, 41.18], p < 0.0001) and decreased libido (OR = 5.40; 95% CI [1.17, 24.87]; p = 0.03). This study indicated that Serenoa repens had the same effect in treating BPH compared with tamsulosin in terms of IPSS, QoL, and PVR after at least 6-month treatment cycle, however, the latter had a greater improvement in PV compared with the former. And Serenoa repens did not increase the risk of adverse events especially with respect to ejaculation disorders and libido decrease.