OBJECTIVES: To examine the interaction between child temperament and caregiver linguistic input (i.e., syntactic complexity and lexical diversity) on receptive language in children who are deaf or hard of hearing (DHH). DESIGN: Families of 59 DHH children ( Mage = 5.66 years) using spoken language for communication participated in this cross-sectional study. Caregivers completed the Child Behavior Questionnaire-Short Form, which measured child temperament across three established factors (i.e., effortful control, negative affectivity, surgency-extraversion) and participated with their child in a semi-structured, dyadic play interaction that occurred during a home visit. Caregivers' language during the play interaction was quantified based on lexical diversity and syntactic complexity. Children also completed norm-referenced receptive language measures (i.e., Comprehensive Assessment of Spoken Language-2, age-appropriate Clinical Evaluation of Language Fundamentals) during the home visit that were combined into a composite measure of child receptive language. RESULTS: When caregivers used lower to moderate levels of lexical diversity, child effortful control was positively related to child receptive language. However, when caregivers used higher levels of lexical diversity, child effortful control and child receptive language were not related to each other. CONCLUSIONS: Family environments rich in caregiver lexical input to children might provide a protective influence on DHH child language outcomes by helping to ensure DHH children with varying self-regulatory abilities achieve better spoken language comprehension. These findings highlight the importance of encouraging caregivers to provide rich and stimulating language-learning environments for DHH children.