The present study aimed to assess the effect of deep band modulation on phrase perception in younger and older adult groups under different signal-to-noise ratios. Study design: A deep band modulation algorithm was used, which increases the modulation depth of the stimuli to reduce the effect of temporal deficits experienced by older adults. Fifteen listeners in each group of younger and older adults participated in the study. A repeated measures design was utilized to investigate the perception of unprocessed and deep band modulated phrases in different signal-to-noise ratios (–9, –7, –5, –3 and –1dB SNR) in the two groups. Results: The deep band modulated phrase perception was significantly better than the unprocessed phrase perception in all SNRs, both in younger and older adult groups. In addition, unprocessed phrase perception was significantly better in the younger adult group than the older adult group. Although deep band modulated phrase perception scores in the younger adult group were better than for the older adults on average, the difference did not reach statistical significance (p > 0.05). Furthermore, the deep band modulated phrase perception scores from different SNRs in the older adult group were found to be close to the unprocessed phrase perception scores in the younger adult group. Conclusion: The findings of the present study indicate that deep band modulation may improve speech perception in noise in older adults.