The aim of this study was to analyze head circumference (HC) growth retrospectively in longitudinally followed growth hormone (GH)-deficient children on GH therapy. Data of 54 (25 F, 29 M) children with GH deficiency were analyzed by dividing the children into two groups: Group 1 with height age (HA) < or =5 years (yrs) (n:18) and Group 2 with HA >5 yrs (n:36). Anthropometric measurements were expressed as standard deviation score (SDS) for chronological age (CA), and HC was also expressed as SDS for CA and HA. Group 1, with CA 6.6 (2.9) yrs at onset of therapy, showed an increase in height SDS from -3.8 (1.4) to -2.4 (1.7) (p < 0.001) and in HC SDS for CA from -1.9 (1.5) to -1.3 (1.6) (p < 0.05) on 4.8 (3.5) yrs of therapy. Group 2, with CA 12.6(2.2) yrs, increased height SDS from -3.4 (1.3) to -2.5 (1.4) (p < 0.001) and HC SDS for CA from -1.2 (1.3) to -1.4(1.2) (NS). HC SDS for HA was -0.4(1.3) in Group 1 and -0.2 (1.1) in Group 2 and showed no significant change. When analyzed by quartiles for cumulative dose of GH, HC SDS for HA became 0.08(1.2) in the fourth dosage quartile (p = 0.043), not significantly different from the mean. HC is disproportionately small for age but normal for the height. GH treatment results in an increase in HC of the children towards normalization in younger children. An increase in cumulative GH dose is associated with an increase in HC, but this is not inappropriate.