An airflow generating device includes a housing and a pressure changing mechanism. The housing has a first opening and a first chamber and contains gas. The first opening is where a first airflow is generated at a first flow velocity. The first chamber is connected to the first opening and is where a second airflow is generated. The second airflow has a second flow velocity which is a highest flow velocity in the first chamber and which is lower than the first flow velocity. A pressure changing mechanism discharges the gas through the first opening while generating the second airflow in the first chamber and the first airflow in the first opening by producing a pressure change in the gas in the housing.