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Introduction: The protein-energy malnutrition is the most prevalent cause of malnutrition and always occures in infants and children under 5 years old. According to the harmful effects of malnutrition, such as high mortality, inability of learning and decrease of mental and physical ability, reconnoite and study of malnutrition qualification is very important.
Material and Methods: This analytic cross-sectional study was carried out on 811 children under 5 years old who were living in rural zone of Arak. Based on health files, clinical inspections and interview with mothers a checklist was fulfilled for every child. Data were analysed by EPI6 software
Results: In this study, none of the children had stricken with Kwashiorkor or Marasmic-Kwashiorkor. Undernourished were seen in 7.39% and Marasmus were also seen in 1.1% of subjects. The prevalence of malnutrition was 7.5% in Wellcome, 33.55% in Waterlow-Stunting, 23.05% in Waterlow-Wasting and 30.94% in Gomez classification. There was statistically correlation between malnutrition and respiratory infection rate, milstones, birthweight, maturity and begning of helpfood (P<0.05).
Conclusion: Considering the results, the most rate of malnutrition in each classification was mild. It is suggested that increasing of familial awareness is an important factor for preventing from next damages and additional treatment costs.