Growth impairment in cystic fibrosis (CF) is worsened by liver disease. Children with CF have serum levels of insulin-like growth factor-I (IGF-I) that are lower than expected for their normal growth hormone (GH) production. In children with CF-related liver disease (CFLD), response to endogenous GH is further reduced. We present our experience with two young children with CFLD given recombinant human GH (rhGH). The first patient was a 5 year-old female with CFLD and poor growth who responded well for 1 1/2 years to rhGH therapy during her initial course and without a significant increase in serum IGF-I, but with a substantial increase in IGF-I concentration when the GH dose was increased. The second patient was a 5 month-old male with advanced liver disease who had transient improved growth and liver function following rhGH. These patients suggest that rhGH is safe and may be effective in children with CFLD.