Treatment of hypercholesterolemic children with restriction of dietary saturated fat may result in an inadequate supply of energy for normal somatic growth. We examined the growth of 30 children with familial hypercholesterolemia, some of whom were also treated with colestipol, a bile acid‐binding resin. The median duration of treatment was 8.5 years in 13 patients on diet only, and 5.5 years + 3.5 years in 17 patients treated with diet followed by diet and colestipol. Statistically significant reductions in serum total cholesterol were obtained in both groups. The SD scores for both height/age and weight/age decreased by approximately 0.4 during dietary treatment (p<0.05), but were not affected by treatment with colestipol. These results document the risk of growth retardation during dietary treatment of children with familial hypercholesterolemia.