To explore factors associated with communication impairments in children with cerebral palsy. Data were obtained on children born between 1999 and 2008 from the Quebec Cerebral Palsy Registry (REPACQ). Out of 535 children with cerebral palsy, 297 were identified to have communication impairments (55.5%). Of these, 96 were unable to communicate verbally (32.3%), 195 had some verbal communication (65.7%), and 6 were unspecified (2.0%). These children were significantly more likely to have a more severe motor deficit (Gross Motor Function Classification System levels IV and V and Manual Ability Classification System levels IV and V), to have spastic quadriplegia or dyskinetic subtypes of cerebral palsy, and gray matter injury on neuroimaging. Communication impairment is a common comorbidity in cerebral palsy and is associated with a more severe motor deficit, spastic quadriplegic or dyskinetic subtype of cerebral palsy, and gray matter injury on neuroimaging. This information allows clinicians to better predict and manage communication impairment in children with cerebral palsy.