Abstract: In the present study, we determined the association between fundal height and actual birth weight. Standard fundal height was measured on 650 pregnant women who were hospitalized in Fayaz Bakhsh and Imam Ali Hospitals in Karaj Iran for delivery. All measurements were performed within the 1 last day of pregnancy. Inclusion criteria were normal and term pregnancy, cephalic presentation of fetus, empty bladder and maternal weight less than 90 kg. For each centimeter of fundal height between minimum (27 cm) and maximum (41cm) at least 30 pregnant women were selected simple randomly and the mean of actual birth weight were calculated for them. A prospective linear regression was found between fundal height and actual birth weight (r=0.72; p< 0.001) correct estimation of birth weight was obtained in 455 (70%) of cases. For actual birth weights in the normal range, our results showed that the normal range of fundal height was 28 to 38 centimeters (macrosomia >38 cm and low birth weight <28 cm). We propose a tape which has a red range (>38 cm) for predicting an macrosom infant, a green range (28-38 cm) for indicating normal birth weight and a yellow range (<28 cm) for indicating low birth weight.