Latar belakang: Desa Karang Tengah, Bagor, Nganjuk merupakan salah satu penghasil bawang merah yang menggunakan pestisida masih tinggi terutama pestisida anorganik. Hasil studi pendahuluan, 65% petani tidak menggunakan peralatan pelindung penuh saat menyemprot dan rata-rata petani melakukan penyemprotan 3-4x dalam seminggu padahal frekuensi penyemprotan yang dianjurkan maximal 2x seminggu. Tujuan penelitian ini adalah untuk mengetahui prevalensi keracunan pestisida petani penyemprotan bawang merah di Desa Karang Tengah Kecamatan Bagor kabupaten Nganjuk.Metode: Populasi penelitian ini adalah petani penyemprot bawang merah Desa Karang Tengah. Sampel penelitian dengan teknik purposive sampling berjumlah 35 responden.Hasil: Hasil pemeriksaan kadar cholinesterase menunjukkan 20% responden tidak normal. Hasil penelitian dari tiga variabel independen, frekuensi penyemprotan, kelengkapan alat pelindung diri , anemia tidak ada hubungan bermakna dengan kadar cholinesterase yang lebih rendah dalam darah petani, tetapi berdasarkan nilai signifikansi dan RP (Prevalence Ratio ) tingkat pengetahuan (α=0,012,PR = 11,5; 95% CI = 1,7 - 77,2), dan lama paparan (α=0,033,PR = 7,5; 95% CI = 1.2–47,7), jumlah jenis pestisida (α=0,021,PR = 9,2; 95% CI = 1,4-59,6), dosis pestisida (α=0,033, PR = 8,0; 95% CI = 1,3 - 50,0), waktu terakhir menyemprot (α=0,001, korelasi koefisien 0,546(kuat)) terdapat hubungan dengan rendahnya tingkat cholinesterase.Simpulan: Kesimpulan dari penelitian ini adalah tingkat pengetahuan, lama paparan, jumlah jenis pestisida, dosis pestisida, waktu terakhir menyemprot berhubungan terhadap kejadian keracunan pestisida dengan penurunan kadar cholinesterase darah petani di Desa Karang Tengah, kecamatan Bagor, kabupaten Nganjuk.Kata kunci: paparan pestisida, kadar kholinesterase, Nganjuk ABSTRACT Title: Prevalence Study of Pesticide Poisoning in Onion Spraying Farmers Karang Tengah Village Bagor District Nganjuk RegencyBackground: Karang Tengah village, Bagor, Nganjuk is one of the producers of onions which uses high pesticides, especially inorganic pesticides. The results of the preliminary study showed that 65% of farmers did not use full protective equipment while spraying and the average farmer sprayed 3-4 times a week even though the recommended frequency of spraying was 2x a week. The purpose of this study was to determine the prevalence of pesticide poisoning by farmers spraying onions in Karang Tengah Village, Bagor Subdistrict, Nganjuk District.Method: The population of the study was farmers spraying onions in Karang Tengah village. Samples of this study with purposive sampling were 35 respondents . Result: The results of examination of cholinesterase levels showed that 20% of respondents were lower. And the result of three independent variables, frequency of spraying, completeness of personal protective equipment used, anemia had no significant association with lower cholinesterase levels in the blood of farmers, but based on the value of significance value and RP (Prevalence Ratio) level of knowledge (α=0,012, PR = 11.5; 95% CI = 1.7 - 77.2), and length of exposure (α=0,033, PR = 7.5; 95% CI = 1.2–47.7), number of types of pesticides (α=0,021, PR = 9.2; 95% CI = 1.4- 59.6), pesticide dosage (α=0,033 PR = 8.0; 95% CI = 1.3 - 50.0), last time spraying α = 0.001, correlation coefficient 0.546 (strong) had significant realtionship for low levels of cholinesterase. Conclusion: The conclusion of this research is the level of knowledge, length of exposure, number of pesticides, the dose of pesticides, last time spraying are related to the incidence of pesticide poisoning with a decrease in blood cholinesterase levels of farmers in Karang Tengah village, Bagor subdistricts, Nganjuk districts. Keywords: pesticides exposure, level of cholinesterase, Nganjuk