A vaporizer includes: a housing having a vaporization cavity arranged therein, an airflow channel being arranged in the housing and in communication with the vaporization cavity; a vaporization assembly accommodated in the housing; an air inlet in communication with the vaporization cavity; and an airflow guide structure arranged in the vaporization cavity between the vaporization assembly and the air inlet for guiding an airflow from the air inlet. The vaporization cavity includes a region between the airflow channel and the air inlet. The airflow guide structure comprises an airflow guide surface arranged at a set angle relative to the air inlet. The airflow guide structure is configured to guide a part of the airflow to the region.