In-wall air purification system capable of supplying purified make-up air and emitting fragrance

The invention relates to an air purification system having functions of supplying purified make-up air and emitting fragrance. The air purification system comprises a circular tube, a built-in circular tube, airflow channels, an air inlet and an air outlet. The circular tube is embedded into a wall. The built-in circular tube is arranged in the circular tube through a circular tube connecting device. The air inlet is nested in the end, adjacent to the outer wall face, of the circular tube. The air outlet is nested in the end, adjacent to the inner wall face, of the built-in circular tube. A photocatalyst filter, an HEPA composite filter, an active carbon fiber, a formaldehyde filter, a fan, a negative-ion generator, a heater and a fragrance device are arranged in the built-in circular tube. A controller is arranged below the air outlet. A filter screen and a closer are arranged in the air inlet. The cylindrical first airflow channel is formed in the air inlet, the circular-tube-shaped second airflow channel is formed between the circular tube and the built-in circular tube, and the cylindrical third airflow channel is formed between the built-in circular tube and the air outlet. Outdoor air enters the air purification system through the first airflow channel, indoor air enters the air purification system through the second airflow channel, and the outdoor air and the indoor air are gathered together to be processed in the third airflow channel through efficient filtration and purification, heating, fragrance addition and negative-ion generation, and then enter a room.