There is provided a medical guidewire which reduces the resistance with a curved guiding catheter, and has improved durability that can keep the resistance reduced for a long time. A core shaft of the medical guidewire has a second cylindrical part, with a smaller diameter than that of a coiled body, on a proximal end side of the coiled body. This second cylindrical part is coated with a hydrophilic material. Further, the hydrophilic material coated on the second cylindrical part has a larger thickness than a hydrophilic material coated on the coiled body.