Using a cardiac conditioning technique, auditory thresholds in walleye pollock Theragra chalcogramma were determined in the presence of masking noise. Signal frequencies of 60, 120, 200, 300, 400, and 500Hz were used. Unfiltered random white noise was introduced as constant background noise. Thresholds ranged from 17 to 66dB above the noise spectrum level in the region of the signal frequency. At the most sensitive frequency (the 60Hz signal), critical ratio (signal/noise ratio) was 17dB, and tends to be larger along with higher frequencies that start lowering the audible sense. It was possible to detect signals in the frequency range of 60 to 500Hz in the presence of background noise. These findings are similar to results from the previous study conducted on cod with similar hearing ability and critical ratios.