A miniature pneumatic device, comprising: a miniature fluid control device comprising a gas inlet plate, a resonance plate, a piezoelectric actuator and a gas collecting plate, wherein the gas inlet plate, the resonance plate, the piezoelectric actuator and the gas collecting plate are stacked on each other sequentially, and a gap g0 is formed between the resonance plate and the piezoelectric actuator to define a first chamber, wherein a difference x between the gap g0 and a vibration displacement d of the piezoelectric actuator is given by a formula: x=g0 - d, and an output pressure of gas is generated when x= 1 μm to 5μm, wherein after the gas is fed into the miniature fluid control device through the gas inlet plate, the gas is transferred through the resonance plate, introduced into the first chamber, and exited from the miniature fluid control device; and a miniature valve device comprising a valve plate having a valve opening and a gas outlet plate, wherein the valve plate has a valve opening, and the gas collecting plate, the valve plate and the gas outlet plate are combined together, wherein after the gas is transferred from the miniature fluid control device to the miniature valve device, a pressure-collecting operation or a pressure-releasing operation is selectively performed, wherein the piezoelectric actuator comprises a suspension plate, an outer frame and a piezoelectric ceramic plate, wherein the suspension plate and the outer frame are connected with each other through at least one bracket, and the piezoelectric ceramic plate is attached on a first surface of the suspension plate, a length of the suspension plate is in a range between 7.5mm and 12mm, a width of the suspension plate is in a range between 7.5mm and 12mm, and a thickness of the suspension plate is in a range between 0.1mm and 0.4mm, a length of the piezoelectric ceramic plate is not larger than a length of the suspension plate, the length of the piezoelectric ceramic plate is in a range between 7.5mm and 12mm, a width of the piezoelectric ceramic plate is in a range between 7.5mm and 12mm, and a thickness of the piezoelectric ceramic plate is in a range between 0.05mm and 0.3mm. a miniature fluid control device comprising a gas inlet plate, a resonance plate, a piezoelectric actuator and a gas collecting plate, wherein the gas inlet plate, the resonance plate, the piezoelectric actuator and the gas collecting plate are stacked on each other sequentially, and a gap g0 is formed between the resonance plate and the piezoelectric actuator to define a first chamber, wherein a difference x between the gap g0 and a vibration displacement d of the piezoelectric actuator is given by a formula: x=g0 - d, and an output pressure of gas is generated when x= 1 μm to 5μm, wherein after the gas is fed into the miniature fluid control device through the gas inlet plate, the gas is transferred through the resonance plate, introduced into the first chamber, and exited from the miniature fluid control device; and a miniature valve device comprising a valve plate having a valve opening and a gas outlet plate, wherein the valve plate has a valve opening, and the gas collecting plate, the valve plate and the gas outlet plate are combined together, wherein after the gas is transferred from the miniature fluid control device to the miniature valve device, a pressure-collecting operation or a pressure-releasing operation is selectively performed, wherein the piezoelectric actuator comprises a suspension plate, an outer frame and a piezoelectric ceramic plate, wherein the suspension plate and the outer frame are connected with each other through at least one bracket, and the piezoelectric ceramic plate is attached on a first surface of the suspension plate, a length of the suspension plate is in a range between 7.5mm and 12mm, a width of the suspension plate is in a range between 7.5mm and 12mm, and a thickness of the suspension plate is in a range between 0.1mm and 0.4mm, a length of the piezoelectric ceramic plate is not larger than a length of the suspension plate, the length of the piezoelectric ceramic plate is in a range between 7.5mm and 12mm, a width of the piezoelectric ceramic plate is in a range between 7.5mm and 12mm, and a thickness of the piezoelectric ceramic plate is in a range between 0.05mm and 0.3mm.