The utility model discloses an air heats automatic temperature -control device in succession in dry production of polymerization, including air cleaner, forced draught blower, fan air volume automaticregulating valve, air heater, steam pipe, steam inlet automatic regulating valve, steam backflow pipe, drying tube, hydrophobic means, the air heater inner heating pipe is that " since " shape is parallelly connected to distribute inside the fan air volume 0 piece, and its fan air volume 1 is comparatively simple, has great heating space and flow area to can suitably increase heating group numberaccording to the heating demand, adopt the beneficial effects of the utility model are that the ventilation air medium can be evenly and steam touched heating pipe fully, and air regulation valve, steam control valve and hydrophobic means's application can make temperature regulating device more accurate, therefore can carry the high pressure heater thermal efficiency greatly and effectively realize the air heating requirement, the utility model discloses but the wide application need be to air heating's temperature regulating device when the different product of production.