Working children often come from marginalize, socially deprived and often high risk backgrounds for lead toxicity. This study was carried out in Zagazig city during the period from September 2003 to January 2004 to estimate blood lead concentrations and some anthropometric measurements among working children to determine the frequency of lead toxicity and its impact on physical growth together with the potential risk factors affecting it in these children. Working child was defined as waged and unwaged male child aged 6-14 years, employed in economic activity in the study area and not attending school. Subjects of this study included 300 male children of age ranged from 6 to 14 years. They were classified into two groups : Group I: included 200 working male children selected randomly from those working in some small-scale workplaces as benzene stations (40) battery repair shops (45), ,mechanic workshops(50), painting (doco) (40) and garages(25). Sampling was stratified so that each category of child labor was represented in the study sample in proportion to its size. Group II: included 100 apparently healthy non working male children served as controls and selected from neighborhoods and relatives of the previous group and properly matched together regarding age, sex and socioeconomic standard. This study revealed that the frequency of lead toxicity(≥10µg/dl) was significantly higher among working children(89.5%)than non working ones(24%) (P