The aim of this study was to determine the frequency of G6PD deficiency and assess its impact on morbidity, especially anemia, in preschool-aged children in Cambodia. A total of 151 children including 82 boys and 69 girls from the Kandal province near Phnom Penh were studied. Ages ranged from 8 to 69 months. Blood was collected in EDTA-coated tubes. Blood counts were performed with an ABX Micros 60 system and G6PD in red blood cells was measured with a Roche Cobas Mira Plus system using Gamma reagents. G6PD deficiency was found in 14 cases (13.4% of boys and 4.3% of girls). Deficiency was complete in 7.3% of children and partial in 2%. Anemia defined as hemoglobin concentration less than 110 g/l was detected in 29.1% of children. No case of anemia could be attributed to enzyme deficiency since no sign of hemolysis was observed in any of the three children presenting both conditions. Further study is needed on G6PD deficiency in Cambodia including malaria-endemic areas and on the frequency and severity of jaundice due to enzyme deficiency in newborns.