The long-tailed nighthawk lives in evergreen broad-leaved forests, shrubs, scrub belts, mangroves, savannas and wetlands. During the day, it often crouches in dense forests or grasslands, and is sometimes seen standing on rocks by the roadside. Because of its small claws, it often moves by jumping on the ground. At dawn and dusk, the long-tailed nighthawk will call for about half an hour on the perch or in flight, and the call is similar to a continuous "tok, tok, tok, tok". When perching on a tree, its body is often parallel to the tree trunk, crouching on the tree trunk. Because its body color is very similar to the color of the tree trunk, it is generally not easy to be found.
Long-tailed nighthawks are active and hunt mostly at dusk, early morning, and at night. Prey include nocturnal insects such as moths, crickets, mosquitoes, termites, beetles and other coleoptera insects, wasps and other small animals. When hunting, long-tailed nighthawks will wait motionlessly, then quietly and swiftly swoop down to catch their prey, and then take a short rest.
This species is very agile and often flies very close to the ground and drifts left and right during hunting. The Long-tailed Nightjar has a special joint on its mandible that allows it to lower its beak even lower during hunting, making it act like a wide shovel for insects. The beak is also surrounded by a circle of bristle-like feathers that act like a brush to move insects into its mouth, preventing them from touching the bird's eyes and reminding the bird to close its beak.
The breeding season for the Long-tailed Nightjar is from March to June each year. During courtship, the two birds approach each other, making low croaking sounds, while the male displays a white crescent pattern on his swollen throat. The male bird does not build a nest. Instead, the female bird will find a shallow depression on the ground as a nest and lay eggs. The eggs are pink, creamy yellow or dark orange-red with light reddish-brown spots. The chicks will have full feathers about 3 weeks after hatching and will be able to fly.