A lubrication structure for a multi-speed transmission has a lubrication structure in which a gear shaft is provided with cam guide grooves in an inner cavity thereof. A lubricating oil is introduced into the inner cavity by way of oil feed introducing holes which are bored in one end portion of the gear shaft so as to provide communication between the inside and the outside of the gear shaft. The lubricating oil is led in the axial direction along the inner peripheral surface of the inner cavity by axial oil feed grooves formed by cutting along the inner peripheral surface of the inner cavity in parallel to the cam guide grooves. The lubricating oil is led out to the engagement switch-over mechanism by radial oil feed holes bored in radial directions so as to communicate with the axial oil feed grooves at axial-direction positions where pin members are located.