To provide a method for manufacturing a separator for a fuel cell, which enables the production under a reduced load while preventing the erroneous detection about the presence or absence of a pin hole.SOLUTION: A method for manufacturing a separator for a fuel cell comprises at least the steps of: ultrasonic cleaning a separator material having a carbon layer on a surface of a base material by passing the separator material through a plurality of cleaning tanks each containing a cleaning liquid sequentially for ultrasonic cleaning; and drying the separator material subjected to the ultrasonic cleaning. In the ultrasonic cleaning step, if the cleaning liquid of the second-to-the-last cleaning tank is over 2.4×10-4 wt% and no more than 0.1 wt% in carbon concentration, and over 0.027 wt% and no more than 1.35 wt% in acryl concentration, and the cleaning liquid of the last cleaning tank is no more than 2.4×10-4 wt% in carbon concentration and no more than 0.027 wt% in acryl concentration, the separator material goes through ultrasonic cleaning in the last cleaning tank under the following condition: E=t×P2 (where E represents an energy (mV2 sec), t represents a time(sec), and P represents an effective sound pressure (mV))>1900.SELECTED DRAWING: Figure 3