Organophosphate and pyrethroid insecticides are used for controlling residential and agricultural insect pests and disease-carrying vectors in Thailand especially in the northern region. Chiang Rai and Nan Provinces are well known for agricultural production. The aim of the present study was to assess the level of exposure to organophosphate and pyrethroid insecticides in 51 consumers and 49 farmers living in Chiang Rai and Nan Provinces by monitoring the urinary metabolites 6-dialkylphosphates (DAPs) and 3-phenoxybenzoic acid (3-PBA) as biomarkers of exposure to organophosphates and pyrethroids. The results showed at least one metabolite was present in all subjects indicating that consumers and farmers were exposed to these pesticides. Concentrations of organophosphate and pyrethroid metabolites in consumers and farmers were similar except diethylthiophosphate which was significantly higher in farmers. Diethyldithiophosphate and 3-PBA concentrations were significantly different between the group who had reported using and not using pesticide in their house.