The machine for machining crankshafts comprises a support (2) to support at least one crankshaft (100), and at least one actuator (1) to actuate a machining tool for machining the crankshaft. The support (2) is configured to hold the crankshaft with at least two clamping devices (21) configured to secure the crankshaft in correspondence with at least two main journals (103) of the crankshaft. The support (2) turns in respect to a vertical axis (A) to modify an angle of attack between a longitudinal axis (B) of the crankshaft (100) and the actuator. The support is provided with a turning mechanism (22) displaceable between a retracted position wherein it does not interact with the crankshaft (100), and an actuation position wherein the turning mechanism (22) interacts with the crankshaft (100) in order to turn the crankshaft (100) in respect to its longitudinal axis (B).