How to Tie a Blood Knot

Joining Two Fishing Lines Together

Fly fishermen love using the Blood Knot because it binds, strengthens, and lengthens two separate pieces of fishing line.

The Blood Knot is actually composed of two knots, each made by the two separate ends of the fishing line. These two knots are so compact they can go through many different types of rod guides with almost no interference. This makes your line casting pretty much unrestricted.

How do you tie a blood knot? It’s simple to learn and can be used over and over again. For the sake of clarity with these instructions, we’ll label the fishing line on the left as Line A and the fishing line on the right as Line B.

How to Tie a Blood Knot

Step 1

• Lay the two fishing line strands down on a clean surface so that Line A is on the left and Line B is on the right.
• Cross Line B over Line A so that they make an “X” shape, with about 6” dangling ends for both lines.

Step 2

• With your right hand, pinch the “X” where the two lines cross.
• With your left hand, take the end of Line B and wrap it underneath Lina A.
• Pull Line B and wrap it again around Line A.
• Make at least four wraps around Line A, moving towards your left-hand side as you do so.
• You should have four separate loops around Line A of Line B cord.

Step 3

• Take the remaining loose end of Line B and pull it up under the “X” intersection of the two lines.
• Holding the two wrapped lines in your left hand, add the loose end of Line B to it, keeping it in place.
• Now we’re going to wrap the end of Line A over Line B.

Step 4

• There is one major difference. With the first wrapping in Step 2, Line B was wrapped under Line A. With this wrapping, Line A will be wrapped over Line B.
• Wrap Line A over Line B four times to create four loops.
• After wrapping, take the final short length of Line A and stick it down through the space next to the final short length of Line B.
• Line B is facing upward and Line A is facing downward.

Step 5

• In your left hand, pinch Line A about one inch from the center knot.
• In your right hand, pinch Line B about one inch from the center knot.
• Gently and steadily, pull your hands so that the center knot tightens.
• You might have to reposition your hands to new pinch points as the knot gets tighter.
• Push the looped wraps of the lines together to form the compact knot.

Step 6

• You should have the two tiny ends of both strands sticking out of the center of the knot.
• Take a pair of scissors and cut those ends off very close to the knot.

Cast Your Line

You can practice tying blood knots on many different types of line. Now, you’re ready to get back to fishing.