A sensor guidewire includes a sensor and a tubular body that covers the sensor. The tubular body includes a proximal blocking wall that is formed on a proximal side of a measurement portion of the sensor, a distal blocking wall that is formed on a distal side of the measurement portion of the sensor, and a hole that extends through the tubular body and through which blood flows into or flows out of the tubular body past the measurement portion of the sensor. The sensor is disposed on a proximal side of the hole. The proximal blocking wall and the distal blocking wall form a measurement chamber in the tubular body, and the sensor does not impede blood flow through the hole.
