There is provided a method and apparatus for forming a drug coating layer capable of preventing breakage of elongated drug crystals on a surface of a balloon and maintaining the drug crystals in an appropriate shape in order to act on a living body. A method for forming a drug coating layer (40) in which a plurality of elongated bodies (42) which are crystals of a water-insoluble drug and each have a long axis are formed on a surface of a balloon (30), and the method includes a step of supplying a coating solution which contains the water-insoluble drug, a water-soluble additive, an organic solvent, and water to the surface of the balloon (30) and evaporating the organic solvent and the water to form an additive layer (41) containing the water-soluble additive and a protruding crystal (48) having a tip end protruding from the additive layer (41), a step of cutting out a surplus portion (49) protruding from the additive layer (41) of the protruding crystal (48) from a part surrounded by the additive layer (41) and forming the part surrounded by the additive layer (41) as the elongated body (42), and a step of removing the cut-out surplus portion (49) from the drug coating layer (40) .
