In this study we investigated the benefit of using hearing aids for Cantonese tone perception among children with various degrees of hearing impairment. Forty-eight children with moderate to profound hearing loss were investigated. They were required to perform a lexical tone perception test with recorded test stimuli presented at 65 dB in soundproof booths. To allow for comparison, the subjects performed the test under 2 conditions: with their hearing aids turned off (unaided condition) and with them turned on (aided condition). The mean tone perception scores for the aided condition were higher than those for the unaided condition across all of the subject groups. Paired sample t-tests showed statistically significant improvement in tone perception in the moderate and severe hearing loss groups (p = .02 and p = .03, respectively). The result obtained from the moderately severe hearing loss group was marginally significant (p = .058). The improvement in tone perception in the profound hearing loss group was insignificant (p = .55). The use of a hearing aid is beneficial for Cantonese tone perception in children who have moderate to severe hearing impairment. When a hearing loss is greater than 90 dB, ie, in children who are classified as having profound hearing loss, a hearing aid is not effective in aiding Cantonese tone perception.