We report a case of suicide due to organophosphate poisoning in an 80-year-old woman who ingested malathion mixed with a fruit drink. She presented with signs and symptoms of cholinergic crisis and initially improved with therapy. Her plasma cholinesterase (ChE) level remained low, her course progressively deteriorated with respiratory and renal failure, and she died 12 days after hospital admission. The antemortem blood malathion level of 23.9 mg/L is the highest reported in the literature, as determined by modern methods. Postmortem toxicologic analysis revealed still greatly reduced ChE activity.