A circular knitting machine for men's socks with needles on the dial comprising a dial needles selector mechanism able to selectively move the dial needles to involve the selected needles in the formation of the stitches and to exclude the needles not selected. In addition the machine is able to repeatedly perform transfer of the stitch from the cylinder to the dial. Moreover, the machine is fitted with a mechanical traction mechanism for tensioning the sock being formed. In addition, the machine presents expedients to limit the deformation of the selector rods and reduce detrimental effects on the actuator or flaws in the formation of the stitch.