Introduction:Delayed reaction following mass hornet envenomation is associated with various clinical manifestations.Case Presentation:The authors present a case of a 24-year-old male from eastern Nepal, who presented following mass envenomation by hornet stings. He had progressive yellowish discoloration of skin and sclera, myalgia, fever, and dizziness. He had passage of tea-coloured urine followed by anuria. Laboratory investigations suggested acute kidney injury, rhabdomyolysis, and acute liver injury. The authors managed the patient with supportive measures and haemodialysis. There was complete recovery of liver and renal function in the patient.Discussion:The findings in this patient were similar to other cases reported in the literature. These patients must be managed supportively, with few requiring renal replacement therapy. Most of these patients recover completely. In low-middle-income countries like Nepal, delay in seeking care and delay in reaching care is associated with severe clinical manifestations. Delayed presentation can lead to renal shutdown and mortality; hence, early intervention is simple, and, crucial.Conclusion:This case highlights the occurrence of delayed reaction following mass envenomation by hornets. Also, the authors show an approach to managing such patients, similar to managing any other case with acute kidney injury. In these cases, an early simple intervention can prevent mortality. It is crucial to train healthcare workers regarding toxin induced acute kidney injury and the importance of early identification and intervention.