The disclosure provides a gas flow detector comprising a conduit, a first and a second pressure gauges. The conduit includes a flexible pipe, a first and a second connecting pipes. The flexible pipe has a contraction portion, a throat and an expanding portion. Further, the throat is sandwiched between the contraction portion and the expanding portion, and the inner diameter of the throat is smaller than that of the contraction portion and the expanding portion. The first and the second pressure gauges are configured to respectively detect the gas pressure of the first connecting pipe and the throat, and the gas flow rates of the first connecting pipe and the throat is calculated from the reading of the difference of the gas pressures. A positive airway pressure apparatus (PAPA) containing the gas flow detector is also disclosed herein.
