An air purifier comprising a housing provided with an air inlet and an air outlet; a filter module; a drive module and a processing module are sequentially arranged in the housing along an airflow direction; the drive module is used to drive the air to flow from the air inlet to the air outlet; the processing module in turn comprises a Titanium dioxide plate and an LED light plate sequentially installed in the housing along the airflow direction; and the LED light plate irradiates the Titanium dioxide plate, the LED light plate irradiating UVA and UVC; characterized in that the housing is provided upright; the housing comprises an inner housing and an outer housing sleeved outside the inner housing; a plurality of the air inlets are provided on an outer wall of the outer housing along the circumferential direction of the outer housing; the air outlet is provided on an upper end of the outer housing and communicated with an inner cavity of the inner housing; a lower end of the inner housing is provided with an air guide port communicated with the inner cavity of the inner housing; an outer wall of the inner housing is provided with convex edges along its length direction; the convex edges, the outer wall of the inner housing and an inner wall of the outer housing form a diversion cavity communicated with the air inlet and the air guide port; and the filter module, the drive module and the processing module are located between the air guide port and the air outlet, and a power supply module is provided between the filter module and the drive module and is installed inside the inner housing, the power supply module comprises a series of battery units that are disposed along the circumferential direction of the inner housing and a mounting seat that comprises a mounting sleeve sleeved outside the battery unit, one mounting sleeve corresponds to one battery unit, and the mounting sleeve is fixedly connected with the inner wall of the inner housing, and a passageway is formed between the mounting sleeves and the battery units, and air from the air inlet to the air outlet flows through the passageway. the housing is provided upright; the housing comprises an inner housing and an outer housing sleeved outside the inner housing; a plurality of the air inlets are provided on an outer wall of the outer housing along the circumferential direction of the outer housing; the air outlet is provided on an upper end of the outer housing and communicated with an inner cavity of the inner housing; a lower end of the inner housing is provided with an air guide port communicated with the inner cavity of the inner housing; an outer wall of the inner housing is provided with convex edges along its length direction; the convex edges, the outer wall of the inner housing and an inner wall of the outer housing form a diversion cavity communicated with the air inlet and the air guide port; and the filter module, the drive module and the processing module are located between the air guide port and the air outlet, and a power supply module is provided between the filter module and the drive module and is installed inside the inner housing, the power supply module comprises a series of battery units that are disposed along the circumferential direction of the inner housing and a mounting seat that comprises a mounting sleeve sleeved outside the battery unit, one mounting sleeve corresponds to one battery unit, and the mounting sleeve is fixedly connected with the inner wall of the inner housing, and a passageway is formed between the mounting sleeves and the battery units, and air from the air inlet to the air outlet flows through the passageway.