Risk assessment traditionally are conducted on individual chemicals; however, humans are exposed to multiple chemicals in daily life. The organophosphotus (OP) pesticides are considered in a single risk assessment because they act by a common mechanism of toxicity, and there is likely to be expose to multiple OP pesticides simultaneously or sequentially. The OP pesticides act by inhibiting the enzyme acetylcholinesterase (AChE) and have available extensive database. AChE is widely distributed droughout the body, most importantly in the nervous system. Inhibition of AChE results in accumulation of acetylcholine in the nervous system that results in clinical signs of cholinergic toxicity, including increased salivation and lacrimation, nausea and vomiting, muscle fasciculation, lethargy and fatigue, among others. To conduct an exposure assessment for pesticides in the diet, we need to know the food consumption patterns of the population, and the pesticide residue levels in the foods that are consumed. This study was conducted to identify cumulative dietary risk due to multiple OP pesticides that can be exposed through various foods. Total 22 food samples including cereals, vegetables and fruits were collected randomly two times from food markets in several sites (4 cities). The subjected foods were selected by regarding of highly consumed foods to general Korean people. The 12 OP pesticides including Acephate, Azinphos-methyl, Chlorpyrifos, and Diazinon were monitored. For the exposure assessment, general adult group of 60 kg body weight was regarded as target population and food consumption data suggested by Lee et al. (2000) were used as consumed value of individual food Analyses of samples for OP pesticides have been carried out according to the multiclass multiresidue analysis method and acephate and methamidophos analysis method of Korea Food Code. In general the levels of OP pesticides found in the food samples were very low or not detected. The detected highest value was 0.282 ppm as methidathion in mandarin and acephate, chlorpyrifos, methamidophos and methidathion were detected in several foods. To quantify simultaneous exposure, toxic equivalency factor of proportionately corresponding potency giving decreased AChE activity on the basis of reference dose 0.3 ㎍/kg/day to the chlorpyrifos was applied. The estimated dietary daily intake of OP pesticide was 4.52 × 10^(-2) ㎍/kg/day as mean value. The hazard index (HI) is the sum for OP pesticides being considered together was 0.15. The HI less than 1 indicates the exposure may be lower than an acceptable level.