Pesticide activated de-iodinase type 3 enzymes (DIO3) and produce reverse Triiodothyronine (rT3). 2017 Reverse T3 influences uptake of cellular thyroid hormone. The study aimed to describe the pesticide exposure and level of rT3 in school children. Method: Subjects were 84 school children who lived in agriculture area in Brebes District, Indonesia. The study used cross-sectional design. Pesticide metabolites in urine were measured by HPLC with Triple Quadrupole Tandem Mass Spectrometry detector. Serum samples were examined by ELISA method for rT3 detection. Data were analyzed using Mann-Whitney tests (α = 0.05). Results: In 51.2% out of 84 subjects, three of six types of dialkyl phosphate metabolite were detected in urine. The type of pesticide metabolites were diethylthiophospate (35.7%), dimethylthiophospate (28.6%), and dimethyldithiophosphate (8.3%). The mean levels of diethylthiophospate were 0.01±0.019 ppm (0.001–0.1 ppm), of dimethylthiophospate 0.015±0.034 ppm (0.001–0.14 ppm), and of dimethyldithiophosphate 0.042±0.013 ppm (0.026–0.064 ppm). The mean level of rT3 was 323.21±193.78 pg/ml (97.22–864.56 pg/ml). All subjects had rT3 above the normal level (25–75 pg/ml). There was a significance different between the mean level of rT3 among school children who were exposed and non exposed to pesticide (p < 0.001). Conclusion: Pesticides exposures are thought to increase the activity of DIO3 and have an impact on increasing the levels of rT3 level in school children in the agriculture area. All subjects may indicate cellular hypothyroidism and needs to be confirmed by assessed free T3/reverse T3 ratio.