The effect of TIG-dressing on fatigue strength in support of the fillet weld of offshore platform was investigated experimentally in the paper. According to the causes in which most cracks are produced in actual structure, the model tests have been performed based upon cruciform weld bead characteristic. The TIG-dressing technique parameters were established by the actual structure and the fatigue specimen tests were done also. The life estimation equation after TIG-dressing is presented by least square method. The fatigue life used by TIG-dressing has increased over 100%. Therefore the TIG-technique gives a big potential for engineering application.