To provide a contamination detection device for a linear motor that can detect contamination immediately when the conductive contamination enters a gap δ between a mover and a stator on the linear motor.

The contamination detection device for the linear motor includes a first power supply to be used for detecting the conductive contamination present at a gap δ between a mover side and a stator side on a linear motor, a short circuit detection circuit to detect the conductive contamination present at the gap δ using the first power supply, a short circuit signal generation circuit to generate a short circuit signal due to the conductive contamination in the linear motor using a detection signal from the short circuit detection circuit, and a second power supply to drive the short circuit signal generation circuit.