Abstract: A building fire escape system, comprising an auxiliary descending device, the auxiliary descending device being a sliding pole (6) or a spiral chute (6?), and at least one refuge chamber, the refuge chamber being a fireproof spatial structure integrated with the building. The inside of the refuge chamber is divided into a first space (2) and a second space (3) by fire partitions (1, 4). The first space (2) communicates with the interior space of the building. The second space (3) communicates with the exterior space of the building. The fire partition (4) is provided with a fireproof door (11) connecting the first space with the second space. Any two neighboring refuge chambers are interconnected. The fire partition is provided with an observation window (12). The first space and the second space are provided with an air supply pipe (14) and an air exhaust pipe (15). Disposed at the top of the refuge chamber is a water tank (16) connected to the fire main pipe (17).