Recent years have witnessed the rapid expansion of the home-sharing business. The home-sharing services provided by Airbnb not only allow the homeowner to earn extra income by renting out part of the property to the potential renters but also provides the renters an authentic travel experience by living with residents. The emerging business model of Airbnb may bring about some uncertainties to rental housing markets. This study aims to explore an important issue – whether the home-sharing services provided by Airbnb would exacerbate the problem of housing affordability in Hong Kong. By examining the data from multiple sources such as the website of Airbnb and Census statistics from the Hong Kong Government, and housing rental transactions from property agents’ website via several econometric methods, we found that (1) the arrival of Airbnb would drive up housing rent rate around 3.6–4%; (2) The Airbnb activities would increase the rent-to-income ratio by 4%–4.7% in Hong Kong; (3) short-term home-sharing provided by Airbnb under current circumstance would lead to housing unaffordability in Hong Kong. It is suggested that regulations/guidelines on home-sharing should set a quota or limit the number of offering from long-term rentals to short-term rentals.