Long-eared owls may divided their hunting into phases, the first stopping around midnight, the second beginning some point after midnight and ending an hour before sunrise.
While hunting, they tend focuses on the edge of woodlands, hedgerows and open spaces with rough grassland, and over young trees and open ground of all kinds.
They hunt mainly on the wing, flying low and fairly slowly, often being quite low to ground, i.e. only  around 150 cm (59 in).
More often than visually finding their prey, it is thought that long-eared owls most often audibly detect the rustling of their intended food.
In lab settings, long-eared owls were considerably more skilled at finding mice by sound in more or less complete darkness than tawny and barred owls (Strix varia), and in some American experiments even outclassed the auditorily-acute barn owls in this regard.
Once prey is spotted, the long-eared owl's flight suddenly stalls, then they quickly drop with talons spread to pounce on prey that is perceived, or especially, that comes out into the open.
Habitat may be perhaps even more key than prey numbers to the selection of hunting grounds.
Often when prey numbers are more ample in timbered areas nearer the roost or rich marshy areas in the vicinity, the long-eared owls will still often come to more prey-poor areas such as old fields so that they can detect prey on open ground.
The footspan of a long-eared owl, including claws, reaches on average 11.3 and 12.5 cm (4.4 and 4.9 in) in males and females, respectively, which would be large for a diurnal bird of prey but is quite small for an owl of its size, given the physiological differences in the way different birds of prey tend to kill their prey.
While acciptrid raptors tend to kill by stabbing with their talons through vital organs, owls are more likely to constrict their prey to death, so tend to have proportionately larger, more robust feet.
In other medium-sized owls, the footspan in tawny owls and barn owls respectively averages 13.4 and 13.2 cm (5.3 and 5.2 in) in between the sexes (notably footspan seems to be a fairly reliable predictor of body mass of an owl as well).
Prey capture by long-eared owls was studied and compared to tawny owls in a European experiment.
The two owl species caught mammals and beetles caught in similar ways but the long-eared owls shied away from flying sparrows and would only capture the sparrows when they perched (though the tawny did not avoid flying sparrows, it too would only capture the prey when perched).
Long-eared owls either disregarded or killed but did not eat amphibians, while tawny owls did catch and eat amphibians when they were available.
Occasionally the tawny owls would attack fish whilst one long-eared owl caught but did not eat a fish.
The European study further revealed that several owls of different species ate bits of plant and did not appear to do so out of food deprivation or hunger.

Taken as whole, the global population of long-eared owls may appear to have a widely varying diet.
One study accrued information from 312 studies from around the species’ range.
In total 478 prey species were found to be described, of which 180 were mammal species, 191 were bird species, 83 were assorted invertebrate species, 15 were reptiles, 7 were amphibians, and reportedly just a couple fish species.
This included a total of approximately 813,033 prey items having been reviewed.
However, on closer inspection, the long-eared owl generally appears to be something of a dietary specialist.
It usually takes primarily, often nearly entirely, small mammals, e.g. rodents, as food in almost every part of its range.
Usually a broad picture emerges that between 80 and 99% of the diet consists of mammals, averaging 94% in one estimate for all of Europe.
However, in warmer, insular or more urbanized environments, a greater percentage or, rarely, even a majority of the diet can locally be non-mammalian prey.
Mean prey sizes have been studied extensively and are almost always fall within a very narrow range.
In Europe, the mean estimated prey size overall
Long-eared owls may divided their hunting into phases, the first stopping around midnight, the second beginning some point after midnight and ending an hour before sunrise. While hunting, they tend focuses on the edge of woodlands, hedgerows and open spaces with rough grassland, and over young trees and open ground of all kinds. They hunt mainly on the wing, flying low and fairly slowly, often being quite low to ground, i.e. only  around 150 cm (59 in). More often than visually finding their prey, it is thought that long-eared owls most often audibly detect the rustling of their intended food. In lab settings, long-eared owls were considerably more skilled at finding mice by sound in more or less complete darkness than tawny and barred owls (Strix varia), and in some American experiments even outclassed the auditorily-acute barn owls in this regard. Once prey is spotted, the long-eared owl's flight suddenly stalls, then they quickly drop with talons spread to pounce on prey that is perceived, or especially, that comes out into the open. Habitat may be perhaps even more key than prey numbers to the selection of hunting grounds. Often when prey numbers are more ample in timbered areas nearer the roost or rich marshy areas in the vicinity, the long-eared owls will still often come to more prey-poor areas such as old fields so that they can detect prey on open ground. The footspan of a long-eared owl, including claws, reaches on average 11.3 and 12.5 cm (4.4 and 4.9 in) in males and females, respectively, which would be large for a diurnal bird of prey but is quite small for an owl of its size, given the physiological differences in the way different birds of prey tend to kill their prey. While acciptrid raptors tend to kill by stabbing with their talons through vital organs, owls are more likely to constrict their prey to death, so tend to have proportionately larger, more robust feet. In other medium-sized owls, the footspan in tawny owls and barn owls respectively averages 13.4 and 13.2 cm (5.3 and 5.2 in) in between the sexes (notably footspan seems to be a fairly reliable predictor of body mass of an owl as well). Prey capture by long-eared owls was studied and compared to tawny owls in a European experiment. The two owl species caught mammals and beetles caught in similar ways but the long-eared owls shied away from flying sparrows and would only capture the sparrows when they perched (though the tawny did not avoid flying sparrows, it too would only capture the prey when perched). Long-eared owls either disregarded or killed but did not eat amphibians, while tawny owls did catch and eat amphibians when they were available. Occasionally the tawny owls would attack fish whilst one long-eared owl caught but did not eat a fish. The European study further revealed that several owls of different species ate bits of plant and did not appear to do so out of food deprivation or hunger.
Taken as whole, the global population of long-eared owls may appear to have a widely varying diet. One study accrued information from 312 studies from around the species’ range. In total 478 prey species were found to be described, of which 180 were mammal species, 191 were bird species, 83 were assorted invertebrate species, 15 were reptiles, 7 were amphibians, and reportedly just a couple fish species. This included a total of approximately 813,033 prey items having been reviewed. However, on closer inspection, the long-eared owl generally appears to be something of a dietary specialist. It usually takes primarily, often nearly entirely, small mammals, e.g. rodents, as food in almost every part of its range. Usually a broad picture emerges that between 80 and 99% of the diet consists of mammals, averaging 94% in one estimate for all of Europe. However, in warmer, insular or more urbanized environments, a greater percentage or, rarely, even a majority of the diet can locally be non-mammalian prey. Mean prey sizes have been studied extensively and are almost always fall within a very narrow range. In Europe, the mean estimated prey size overall 
Long-eared owl