An air flow meter comprises a main passage for an axial main air flow; an axial subpassage for air flow, disposed in the main passage and formed so that part of the air in the main passage is taken in at an upstream side thereof and flows in the same direction as the axial main air flow; a radial subpassage for air flow, intersecting the axial subpassage at a downstream side of the axial subpassage so that air from the axial subpassage flows into the radial subpassage and is divided into two radial air flows running in different radial directions; the air having passed through the radial subpassage joining the axial main air flow. An air flow sensing means is disposed in the radial subpassage for sensing a flow rate of air therein, and a projection is disposed in the radial subpassage around the intersection of the axial and radial subpassages, for suppressing turbulence of air flow around the intersection.