The insect order Hymenoptera consists of many medically important groups of stinging insects—Apoidea (bees), Vespoidea (paper wasps, hornets and yellow jackets commonly referred as wasps and Formicidae (ants) . Hymenoptera venoms are concentrated and highly complicated mixtures of biochemically active agents . Though allergic manifestations to Hymenoptera stings are well documented, the complication of acute renal failure (ARF) is rare . Severe reactions to ‘Hymenoptera’ stings are generally attributed to allergic mechanisms. In cases of multiple stings, severe reactions and even death may result from the toxic actions of venom . ARF results mostly from toxic or ischaemic acute tubular necrosis (ATN) in a setting of haemolysis, rhabdomyolysis or both. Rarely, it occurs as a direct nephrotoxic effect of venom or from acute allergic interstitial nephritis (AIN) from hypersensitivity reaction to venom . Besides renal impairment, other systemic complications such as liver impairment, respiratory and cardiac impairments have also been reported . Here, we report three cases of ARF followed by multiple hornet stings during the month of August in 2010.