Provided is a medical bladed device reduced in piercing resistance by coating with a silicone. Also provided is a coating method by which a satisfactory silicone coating is formed on a medical bladed device. A medical bladed device (knife (A)) having a cutting portion (1) with an edge (3) on the periphery thereof and a shank (2) is subjected to coating to coat the cutting portion (1) including the edge (3) with a silicone having a thickness of from 25 nanometers to 5 micrometers. While holding the medical bladed device, with the cutting portion (1) lower and the shank (2) upper, the cutting portion is immersed in a silicone solution so that the angle between the upper or lower side of the cutting portion and the solution surface (21) of the silicone solution is 0-90 degrees. Thereafter, the medical bladed device is raised at a rate of 500 mm/min or less while keeping the angle in that range to separate the cutting portion from the silicone solution. The cutting portion is then dried at a temperature in range of 100-250 °C for 30 minutes or longer. The silicone concentration is 0.2 -15 % by weight, and the thickness of the silicone film is regulated by conducting the coating operation once or repeatedly.
