Ligation may refer to:

• Ligation (molecular biology), the covalent linking of two ends of DNA or RNA molecules
• Chemical ligation, the chemoselective condensation of unprotected peptides
• In medicine, the making of a ligature (tie)
• Tubal ligation, a method of female sterilization
• Rubber band ligation, a treatment for hemorrhoids
• In coordination chemistry, making a bond between a ligand and a Lewis acid
• In orthodontics, a method of attaching the archwires to the brackets
• KAHA Ligation
• Ligation-independent cloning
• Typographic ligature forming