This longitudinal study compares concept vocabulary knowledge of children with cochlear implants (n = 40) and children with hearing aids (n = 30) to that of their typical hearing peers (n = 40). Participants completed the Bracken Basic Concept Scale: Expressive (BBCS:E) at ages 4 and 6. Results revealed significant differences in concept vocabulary knowledge between both groups of children who are deaf or hard of hearing (DHH) and the typical hearing group. Although all groups improved BBCS:E test performance between ages 4 and 6, the rate of improvement in children who are DHH did not trend toward catching up over time. Omnibus expressive vocabulary outcomes predicted BBCS:E performance, but age of amplification did not. These preliminary data suggest persistence in concept vocabulary deficits in children who are DHH and developing spoken language, at least through entry into elementary school.