In Hong Kong, students are expected to speak fluent Cantonese, Putonghua, and English. However, the curriculum does not include Cantonese studies, as children are expected to have already acquired Cantonese by the age of school entry. This study examined the language outcomes of Cantonese-speaking deaf or hard-of-hearing children who attend primary schools within the Hong Kong educational system and considered whether the system currently meets the needs of these children. The Hong Kong Cantonese Oral Language Assessment Scale, which comprises six subtests, was used to assess 98 children with mild to profound hearing loss. A regression analysis was used to examine the influences of various variables on oral language performance in these children. Notably, 41% of the participants had achieved age-appropriate oral language skills, while 18% and 41% exhibited mild-to-moderate or severe oral language impairment, respectively. The degree of hearing loss and the use of speech therapy were identified as significant negative predictors of oral language performance. The issues of a relatively late diagnosis and device fitting, as well as the very poor oral language outcomes, strongly emphasize the need for policy makers to reconsider the existing educational approaches and support for deaf or hard-of-hearing children. Copyright © 2019 The Author(s). Published by Oxford University Press. All rights reserved.