To provide a low-cost shift mechanism of a manual transmission allowing comfortable operation by constituting a shift inner lever member having a pair of arms with one member.

In the shift mechanism of the manual transmission, an annular groove 21d is formed on the outer periphery between the arms 21b and 21c of the cylinder part 21a of the shift inner lever member 21, and a pair of plates 21e, 21e parallel to each other are placed at the bottom surface of the annular groove 21d. A mounting part 23a of an interlock member 23 has an annular shape with a cutout 23a1 formed in a part thereof, and engaged with the annular groove of the shift inner lever member on the inner surface to be relatively rotatable around the axis and not relatively displaceable in the axial direction. In this case, the width of the cutout is set larger than the distance between a pair of places of the shift inner lever member.