We investigated whether the presence of cue tone affected the psychophysical frequency selectivity. We measured masked thresholds with/without the presentation of cue tone in notched-noise in a simultaneous masking experiment or band-pass noise in a simultaneous masking experiment, and then estimated the shapes of auditory filters from these data. Filter-Qs were calculated from the derived filters to compare the tuning of the filters with/without the cue tone. As a result, we found that the tip of the derived filter was sharpened by the presence of cue tone as signal levels were low and the range of improvements was limited to around the signal frequency. This suggested that the presence of cue tone may affect improvements in the psychophysical frequency selectivity.