Objectives: This study assessed the effectiveness of Hwanggigyejiomul-tang for postoperative breast cancer-related lymphedema (BCRL) by a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods: A search was conducted using keywords such as "breast cancer", "lymphedema", "edema", "Huangqi Guizhi Wuwu decoction", "Huangqi Guizhi Wuwu tang", and "Hwanggigyejiomul tang" in 10 databases (PubMed, Cochrane, ScienceDirect, CNKI, CiNii, RISS, KISS, ScienceON, OASIS, DBpia) on February 11, 2024. There were no limits on the publication period and language, and the quality of the studies was evaluated using Cochrane's risk of bias tool. A meta-analysis was performed based on the outcome measurements, such as total effective rate (TER), increase in shoulder joint mobility (flexion, extension, abduction, adduction), Fugl-Meyer assessment (FMA), and visual analog scale (VAS) using Review Manager Web. Results: Eleven RCTs were selected. The treatment group (Hwanggigyejiomul-tang-gagambang or hapbang with control group intervention) showed a more statistically significant effect compared with the control group (physical therapy or western medicine) in TER (upper limb circumference change), TER (upper limb edema grade change), increase in flexion angle, increase in extension angle, increase in adduction angle, FMA, and VAS. Conclusions: Hwanggigyejiomul-tang is effective in treating postoperative BCRL. However, because of the low quality of the included studies, more clinical studies are required to increase the possibility of clinical use.