To provide a drive controller for the crushing machine which has a simple configuration, eliminates light clogging of the crushed product automatically and improves the working efficiency.

A crushing machine comprises a crushing unit 5 crushing a target material, a vibration feeder 4 arranged adjacent to the crushing unit 5, a side conveyer 3 disposed below the vibration feeder 4 and carrying fine grains sieved by the vibration feeder 4 out of the vehicle, a driving pressure detection means 2 of detecting the driving pressure of the side conveyer 3 and a control means 1 controlling at least the operation of the side conveyer 3. The control means 1 has an excessive load-determining means 1a of determining whether or not the side conveyer 3 remains excessively loaded based on the driving pressure detected by the driving pressure detection mechanism 2 and a conveyer reversion controlling means 1d of driving the side conveyer 3 reversely when the side conveyer 3 is determined to remain excessively loaded by the excessive load-determining means 1a.