Background: Anaphylaxis has been increasing in developed countries but there is very little published data on the burden of anaphylaxis and the pattern of adrenaline autoinjector (AAI) prescription from Asia. Objectives: We aim to determine the incidence rates of anaphylaxis and prescription rates of AAI over the past decade in Hong Kong. Methods: Using a centralized electronic database of Hong Kong’s sole public-funded healthcare provider, we obtained and analysed all patients between 2009 and 2019 with physician-reported diagnosis of anaphylaxis. Incidence rates were calculated using population statistics as the denominator. Patients’ prescriptions on discharge were collected to determine the AAI prescription rates. Results: The overall 10-year estimated incidence rate of anaphylaxis was 3.57 per 100,000 person-years. An increasing trend over time across both pediatric and adult populations from 2009 to 2019 was found which was more marked among the pediatric population. There was an overall increasing rates of AAI prescription for patients admitted for anaphylaxis, but the overall AAI prescription rate was less than 15% and was significantly less likely to be prescribed for the adult compared to pediatric patients (36.5% vs. 89.4%, p<0.001). Conclusions: An increasing trend of anaphylaxis incidence rates over the past decade is evident in Asian populations, with a discrepantly low rate of AAI prescription, particularly in the adult patients.