In a resist reflow measurement key, and method of fabricating a fine pattern of a semiconductor device using the same, the resist reflow measurement key includes a first reflow key including a plurality of first pattern elements each having a first pattern with a first radius of curvature located on a first side of a first center line and a second pattern with a second radius of curvature located on a second side of the first center line, and a second reflow key including a plurality of second pattern elements each having a third pattern with a third radius of curvature located on a first side of a second center line and a fourth pattern with a fourth radius of curvature located on a second side of the second center line, the second reflow key being formed on a same plane of a substrate as the first reflow key.