Hereditary angioedema (HAE) is a rare genetic disorder caused by deficiency or dysfunction of C1-esterase inhibitor that is characterized by recurrent episodes of bradykinin-mediated edema. Lanadelumab has been the only available first-line therapy for long-term prophylaxis (LTP) of HAE in China since its approval in 2020. The present study aimed to investigate the clinical efficacy and safety of lanadelumab for LTP in Chinese patients. A retrospective clinical data were collected for the 6 patients and used to examine the frequency of attack symptoms, disease-related loss of work days, and quality of life before and after LTP with lanadelumab. Health-related quality of life was assessed using the Dermatology Life Quality Index (DLQI) and the Angioedema Quality of Life Questionnaire (AE-QoL). Lanadelumab led to reductions of 97.8% and 98.5% in the attack rate and treated attack rate, respectively. All patients exhibited significant improvements in AE-QoL and DLQI scores (100% reduction rates) during the early treatment period (4 weeks and 2 weeks, respectively) and in missed work days/year (98.9% reduction rate). The efficacy of lanadelumab remained stable during COVID-19 vaccination and infection. No serious/severe treatment-emergent adverse events occurred during lanadelumab treatment. This study is the first report that demonstrates the clinical efficacy of lanadelumab and safety of LTP in HAE patients from Chinese mainland. A reasonable dosage plan can ensure a quick and long-lasting protective role of lanadelumab against HAE attacks, during COVID-19 pandemic period.