Abstract: To study the effects of mother's blood lead on new born baby,we followed up newly-married women,collecting their blood before preg nancy,mid-preg nancy,right before giving birth,and blood from umbilical cord.Aseries of IQtests for MDI and PDIwere followed since 6 months of the baby's age with an interval of 6 months1 Step-wise regression and correlation between blood lead levels of different times and the IQ scores of the baby at dif-ferent ages were analyzed.Results showed that the log mean levels of blood lead before pregnancy,in mid-pregnancy,riglht before giving birth,and from umbilical cord were 11.58μg/dl,9.23μg/dl,8.28μg/dl and 7.70μg/dl respectively.The baby's average IQ scores((MDI+PDl)/2)at 6,12,18,24,and 30 months of age were 103.19,108.66,104.81,112.22,113.76 respectively.Negative correlation between mother's blood lead levels and baby's IQ scores were observed.Conclusion is that high level of mother's blood lead has adverse effects on baby's development in intelli-gence and genius movement.