A device for digging and backfilling of ditches, in particular for laying pipes, comprising an automotive travelling mechanism (2) carrying a machine frame (4) with an upper structure, a boom (6) pivoted on the machine frame (4) and having a plurality of boom arms (8, 10, 12) connected with each other with hinges and an excavator bucket (16) pivoted on the free end of the boom (6) is provided with a milling/mixing rotor (22) mounted to the excavator bucket (16).