The coronavirus disease 2019（COVID-19）has now caused a global pandemic since it appeared in December 2019. According to the latest Diagnosis and Treatment Protocol for COVID-19 in China，the possibility of aerosol transmission exists under the condition of prolonged exposure to high concentrations of aerosol in a relatively closed environment. Aerosols are suspensions in air of solid or liquid particles. Due to their small aerodynamic diameter，bioaerosols are prone to deposit in the lower respiratory tract and are more likely to cause severe diseases such as pneumonia than droplets. This review will brush up on the literature on bioaerosols and expound its implications for the protection of COVID-19.