Port wine stain (PWS) is a congenital and progressive capillary malformation characterized by structural abnormalities of intradermal capillaries and postcapillary venules. The visible manifestation is often considered a disfigurement and the accompanying social stigma often causes serious emotional and physical impact. Hematoporphyrin monomethyl ether (HMME) is a newly authorized photosensitizer for treating PWS in China. Hematoporphyrin monomethyl ether photodynamic therapy (HMME-PDT) has successfully treated thousands of Chinese patients with PWS since 2017, and HMME-PDT may be one of the most promising strategies for the treatment of PWS. However, there are few reviews published about the clinical use of HMME-PDT. So in this article, we want to briefly review the mechanism, efficacy evaluation, effectiveness and influencing factors, and the common postoperative reactions and treatment suggestions of HMME-PDT in the treatment of PWS.