An air-puff type intraocular pressure measuring device includes an optical measuring unit and a puffing unit. The optical measuring unit includes an imaging optical path having a perforated lens and an image sensor capable of receiving an eyeball image via the perforated lens for eyeball alignment; a measuring optical path having a measuring element for transmitting a measuring signal and receiving a reflected signal via the perforated lens to derive an intraocular pressure value; and a beam splitter for the image sensor and the measuring element to respectively form a first and a second path having different axial directions. The puffing unit is connected to the optical measuring unit for puffing air through the perforated lens against an eyeball. The puffing unit has a puffing path located coaxially on the second path of the measuring optical path, so that measuring errors caused by parts-related tolerances are effectively reduced.