The utility model discloses a ventilation unit of energy saving building, including ventilated box, air -supply line and play tuber pipe, the upper portion symmetry of ventilated box's the left and right sides is equipped with the air -supply line, ventilated box's top is equipped with electric telescopic device and battery, electric telescopic device's bottom is equipped with the telescopic link,the other end of telescopic link pass ventilated box the roof and with piston board fixed connection, the side cover of piston board is equipped with seal sliding sleeve, the bottom fixedly connectedwith of piston board and air -supply line are corresponding turns to the boss, ventilated box's inner chamber bottom is equipped with slow wind device, ventilated box's bottom through connections goes out the tuber pipe, ventilated box's top is equipped with the sphere cover, sphere cover surface is equipped with solar cell panel, the utility model discloses a control to the piston board realizesclosing at any time whole ventilated box, simple structure, simple operation, the quick wind that flows is before the entering is indoor, through the effect of delaying the wind device for the wind speed declines to a great extent, slow air current, and by electric heat net even heating, the heating effect is showing and is improving.