NiTi shape memory alloys (NiTi-SMA or Nitinol) have successful application thanks to their excellent and unique material properties. However, considering the practical application to human body, elution from the toxic Ni ions into human body should be taken into account. Many researchers have dealt with the issue and already proposed various surface treatment techniques including the surface oxidation and ion implantation.Our focus is to enhance the functionality of Nitinol. We have been developing the smart sensor utilizing metal-containing Diamond-like Carbon (Me-DLC) thin coating. Emphasis can be made on the unique properties of Me-DLC deposited on the Nitinol. Strong adhesive strength has been obtained in Me-DLC and Nitinol system. In this paper, we propose a novel Me-DLC coating with multifunctionality of the suppression of the toxic Ni ions. The paper includes deposition technique, performance of the coating concerning adhesive strength and suppression of the toxic Ni ions, and finally multilayered structure aiming at multifunctionality.