Abstract.The effect of the intravenous glucose on plasma levels of glucagon and insulin were evaluated in thirty‐five LBW preterm infants who were appropriate for gestational age. Their mean birthweight and gestational age were 1220·55 g (range 750‐1730 g) and 29·1 weeks (range 25–35 weeks), respectively. A 30 min glucose infusion in 16 infants (1 g/kg b. w. in 30 min) caused a prompt and sustained suppression of plasma glucagon and a delayed but significant insulin release. The mean of the sum of maximal plasma glucagon decrements below the baseline was 173·42 pg/ml. In another 12 infants a significant fall in plasma glucagon and a variable but significant plasma insulin release also occurred throughout the 24 h study on continuous intravenous glucose (rate 2.4‐2.7 mg/kg/min). The mean of the sum of maximal plasma glucagon decrements below the baseline up to 12 h was 282·36 and was similar to that seen in the pre