Creep deformation localization is a corrimon occurrence generally found in high terriperature components. typically at weldments and geometrical discontinuities. The deformation in a srriall region cannot be measured by a conventional displacement gage. A new technique for measuring long-term local creep deformation was developed. It uses quartz optical fiber marking. remote monitoring. and image processing. Long-terrn measurements of the creep deformations of base metal. weld metal. and heat-affected zone in cross-weld specimens were performed at high temperature. which verify the new technique. Strain distributions and evolutions in the weldrrients are obtained.