The utility model relates to a reheating separate-control phase change air preheating system comprising an air preheater (3), and a smoke channel (4) and an air channel (5) both connected to the air preheater, wherein a low-temperature heat release device (22) and an air reheating heat absorption device (6) are arranged in front of and behind the air preheater (3) on the air channel (5) in an air flowing direction, respectively; a high-temperature heat absorption device (8) is arranged in front of the air preheater (3) on the smoke channel (4) in a smoke flowing direction; a steam main pipe (19) connected with the low-temperature heat release device (22) is communicated with the air reheating heat absorption device (6) and the high-temperature heat absorption device (8) through branch pipes, respectively; and a condensed water main pipe (20) connected with the low-temperature heat release device (22) is communicated with the high-temperature heat absorption device (8) and the air reheating heat absorption device (6) through branch pipes, respectively. The reheating separate-control phase change air preheating system is capable of flexibly adjusting the waste heat recycling quantity and the smoke exhaust temperature based on the change of coal season and unit load.