The skinfold thickness is a good measure of nutritional assessment. The present chapter describes the effects of undernutrition on five skinfold thickness (triceps, biceps, suprailiac, subscapular and thigh) in Bengali primary school girls. Total 168 girls (5-12 years) of four primary schools of north Kolkata were examined. The undernourished girls were identified using height-for-age reference values of WHO taking -2 Z-score as cut-off point. The growth pattern of different skinfolds from the mean values of each skinfold parameter in different ages of well-nourished and undernourished girls were compared with the NHANES reference data. Pearson's correlation study was used to evaluate relationship between two different skinfolds in well-nourished and undernourished girls. The mean values of TrSF and BcSF in undernourished girls were significantly lower than that of well- nourished girls. The mean values of TrSF in undernourished girls were placed under 5th percentile values of NHANES standard. There was no significant difference in SpSF, SbSF and ThSF between well-nourished and undernourished girls. The growth curves of SpSF, SbSF and ThSF were located around 25th, 50th and 50th percentile of NHANES reference data, respectively. Significant correlations between TrSF and ThSF, and SpSF and ThSF were found in the undernourished girls but in the well-nourished girls the SpSF and BcSF were only significantly correlated. TrSF is found to be the sensitive marker for undernutrition in Bengali primary school girls. © 2013 by Nova Science Publishers, Inc. All rights reserved.