Blisk production method and blisk intermediate product

This blisk production method comprises an intermediate product formation step for forming a blisk intermediate product that has: a disk-corresponding part having a circular plate-like shape; a plurality of rotor vane-corresponding parts; and bridges that each link a pair of the rotor vane-corresponding parts adjacent to each other, between a front edge of one of the rotor vane-corresponding parts and a rear edge of the other rotor vane-corresponding part. This blisk production method further comprises: a disk finishing step for, by machining the disk-corresponding part, finishing the disk-corresponding part into a disk in a product form; and a rotor vane finishing step for, by machining the bridges, finishing the respective rotor vane-corresponding parts into rotor vanes in a product form.