Abstract: A medical device having a highly biocompatible surface wherein hydrophilic polymer is bonded onto a surface of the medical device covalently through a nitrogen atom, and a method for manufacturing a medical device having a highly biocompatible surface comprising the steps of applying a hydrophilic polymer having azido group and/or a composition comprising a compound having at least two azido group and a hydrophilic polymer onto the surface of the medical device, and irradiating the biocompatible material with light so that the hydrophilic polymer is bonded to the medical device surface. The device has sufficient biocompatibility, medical functional capability and economical efficiency. The method easily provides a medical device with sufficient biocompatibility without impairing the device's medical functional capability and economical efficiency.