A fly lure or Fly, in terms of sport fishing and fly fishing, is an artificial lure tied with thread, feathers, and hair. Many fly fishers tie their own flies, either following patterns in books, real nature examples of insect, or using their own imagination.

Fly tying is becoming common practice in fly fishing. The technique involves attaching small pieces of feathers, animal fur and other materials on a hook in order to make it attractive to fish. This is made by wrapping thread tightly around the hook and tying on the desired materials.

There are four main categories of flies: dry fly, wet fly, nymph and streamer fly.

Certain fly lures, such as streamers may be used with a normal sport fishing rod, but a special and much softer fly fishing rod is required for most of the fly fishing. The fly fishing technique involves casting out some fishing line in the air and letting it go at the right moment over the river and then letting the fly float on the water with the currents.