A portable blowing device configured for being worn around a neck of a human body, includes two arms each defining an airflow channel therein; and fans received in the arms respectively. The arm includes an inner side wall close to the neck and an outer side wall connected to the inner side wall. The arm includes an air inlet and an air outlet in communication with the airflow channel respectively. The air inlet is arranged at the inner side wall and/or the outer side wall. The fan is configured to generate an airflow passing through the air inlet, the airflow channel and the air outlet in sequence.