A machine for fitting metal runners on a drawer comprises an actuator (44) for mechanically operating at least one hammer (24) for clinching gripping tabs against a side panel (16) of the drawer. The gripping tabs are laterally disposed along a longitudinally extending U-shaped groove formed in the runner (12) and extending from a longitudinal edge of the runner towards the hammer, prior to clinching. The hammer (24) and the corresponding anvil counter plate (22) extend in a longitudinal direction to the runner to simultaneously clinch all the gripping tabs. Advantageously, the machine comprises two clinching assemblies (20) to clinch both runners to a drawer in a single operation.