In order to rapidly screen toxic chemicals in a small amount of biological sample collected from an intoxicated patient at bedside, a simple screening system was developed. The following chemicals were identified for screening: carbamate, methanol, glufosinate, organophosphorus pesticide, bromvalerylurea, salicylate, arsenide, benzodiazepine, methamphetamine, barbiturate, tricyclic and tetracyclic antidepressant, acetaminophen, paraquat, cyanide and theophylline. In this study, all of the above chemicals except theophylline were analyzed by the screening system. Theophylline concentration in blood is routinely monitored at clinical laboratories, so it was not analyzed in this study. Screening methods used were 7 kits and 2 reactions. Fourteen toxic chemicals in 1 ml of urine sample and serum sample were screened in about 2 hr. The proposed screening system was applied to 4 different cases of intoxication by organophosphorus pesticide, acetaminophen, paraquat and glufosinate. Each toxic chemical was detected. This proposed screening system seems to be useful to rapidly screen toxic chemicals in a small amount of biological sample collected from an intoxicated patient at bedside.