Aluminium phosphide (AlP) is a toxic pesticide accompanied by a high mortality rate after acute exposure from different routes. Objectives: evaluation of blood level of lactate, pyruvate and lactate/pyruvate (L/P) ratio as outcome predictors of AlP poisoning. Methodology: All patients with a confirmed diagnosis of acute AlP poisoning who admitted to Poison Control Center- Emergency Hospital-Tanta University, Tanta, Egypt, from October 2019 to end of November 2019 were included. All studied patients (46) underwent thorough history taking, physical examination and routine laboratory investigations. Three mL of blood were used for determination of lactate and pyruvate levels. Results: The predominant manner of poisoning was suicidal due to ingestion of AlP tablets. The mortality rate was 73.9%. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded with statistical significant difference between both studied groups. Oxygen saturation, pH, HCO3, PO2, mean blood hemoglobin, potassium (K) and magnesium (Mg) were statistically reduced in non- survival group compared with survival group. Lactate and L/P ratio showed significant rise in non-survived patients, while pyruvate presented statistically non-significant difference between the studied groups. The blood pH had the highest discriminatory power as regards mortality, followed by DBP on admission, then SBP on admission, lactate, L/P ratio, respiratory rate and pyruvate. The blood lactate and L/P ratio had 100% sensitivity and 66.7% specificity. Conclusion: Blood lactate level was indicated as an outcome biomarker of acute AlP poisoning.