Abstract: The present study was designed to investigate outcomes and predictors of mortality in cases of acute anticholinesterase insecticide poisoning. One hundred cases diagnosed to have acute Organophosphate (OP) toxicity and admitted to Poison Control Center (PCC) were included in the study. Two sheets, one before and the other 24 h after therapy were used for each patient. These sheets included (1) Sociodemographic, (2) Clinical and (3) Investigations; thereafter 5 mL of venous blood were collected on admission after the diagnosis but before any medications were given. Another sample was obtained 24 h later after medications. Serum was used for estimation of pseudocholine esterase level, liver and renal function tests, tests for acute pancreatitis, serum electrolytes, fasting and postprandial glucose levels. Intoxicated cases were mainly males, less than 20 years, residing in urban areas, cause was mainly suicide; delay time correlates with severity; cholinesterase levels negatively correlated with severity. There was powerful, inverse, significant correlation between cholinesterase levels and glucose, lipase, creatinine, Alanine Transaminase (ALT) and Aspartate Transaminase (AST). Morality rate was 7%; one in the moderate group and 6 cases in the severe group (24%). Serum cholinesterase, delay time, sodium, glucose, amylase, lipase, SGPT and alkaline phosphatase, measured on the first day can be used as predictors of mortality in studied cases. Delayed time is the powerful single predictor, followed by lipase and alkaline phosphatase. The delay time was the most useful single predictor of mortality in the present study.