The invention relates to a dip angle compensation gravity open type buffering and pressure relieving device. The device comprises a pressure buffer chamber, a rotary powder discharge channel formed in the bottom of the pressure buffer chamber, an overturned top cover arranged at the top of the pressure buffer chamber, and a pull rope counterweight mechanism connected with the overturned top cover; the pressure buffer chamber is provided with an intake port and an exhaust port; and the intake port and the exhaust port are respectively connected with a dust removing pipe of a dust remover. Compared with the prior art, the device is simple and compact in overall structure and excellent in economy and practicability, achieves the function of responding to normal working conditions, fluctuated working conditions and abnormal working conditions, needs no external energy, sensor and maintenance, is not only suitable for places using negative-pressure dust collecting systems for dust generated in the manufacturing industry, is but also suitable for normal-pressure or micro-positive-pressure blow-off pipes for generating flammable/explosive gas, and is wide in application range and excellent in application prospect.