We evaluated the effectiveness of a two-generation preschool programme (centre-based early childhood education, parenting education and family support) on receptive language skills in children living in culturally diverse families with low income. Using a with-in subject pre-test/post-test design, children (N = 112) showed a statistically significant improvement in receptive language skill as measured by the Peabody Picture Vocabulary Test, Third Edition. At post-test, the children continued to score below typically developing children of the same age. There were no statistically significant differences on receptive language skill with regard to child gender, culture, caregiver education, nor involvement in child welfare services. Only for children of Aboriginal ancestry (n = 40) was the amount of time spent in the programme significantly correlated with the amount of positive change in receptive language skill. When designing early intervention programmes for families with low income, targeting the specific needs of cultural sub-groups may improve outcomes. (Contains 1 figure and 3 tables.)