This study retrospectively analyzed demographic factors that may affect the prevalence of intestinal parasites among Guatemalan school children. The findings of the study showed that young age, wet season, female gender, and severe malnutrition all correlated positively with increased rates of infection. Clinical visits were performed on 10,586 school children aged 5-15 years over a four-year period (2004-2007) in the Palajunoj Valley of Guatemala, during which 5,705 viable stool samples were screened for infection with the following parasites: Ascaris lumbricoides, Giardia lamblia, Entamoeba histolytica, Hymenolepis nana, and Blastocystis hominis. The average overall prevalences of infection for specific parasites were A. lumbricoides 17.7%, E. histolytica 16.1%, G. lamblia 10.9%, H. nana 5.4%, and B. hominis 2.8%. Statistical analysis showed significantly higher rates of infection among younger children with G. lamblia (odds ratio [OR]=0.905, 95% confidence interval [CI] 0.871-0.941, p<0.0001) and E. histolytica (p=0.0006), greater prevalence of H. nana among females (OR=1.275, CI 1.010-1.609, p=0.0412), higher infection rates during the wet season for E. histolytica (p=0.0003) and H. nana (OR=0.734, CI 0.557-0.966, p=0.0275), and greater rates of infection with G. lamblia among malnourished children (for moderately malnourished children OR=1.498, CI 1.143-1.963, p<0.0001) and E. histolytica (for mildly malnourished children OR=1.243, CI 1.062-1.455, p=0.0313). The results suggest that the prevalence of gastrointestinal parasites among young Guatemalan children is highly dependent on the specific species of the parasite.