There are various views on the origin of its name 'Hanase' (flower back): some is that the pass was called 'Hana no se' (the back covered with flowers) as it runs through the heart of Mt. Kita which have been famous for beautiful flowers, others is that the pass is located at so-called north backbone of Kyoto which was 'Hana-no-miyako' (the capital city flourishing), and so on.
名前の由来は花の美しい北山の懐にあるので「花の背」とよばれたから、花の都京都の北の背骨に位置するところにあるからなど諸説ある。