Objectives: To demonstrate effective diagnostic method and proper management of recurrent thyroid cancer through to compare treatment and surveillance of $I^{131}$ scanning detected recurrence and clinically detected recurrence. Material and Methods: We retrospectively analyzed clinical information about 46 patients who has recurrent thyroid cancer of 298 patients who have been primarily operated due to thyroid cancer in PMC at the over 10 years between 1986 and 1995. We examine incidence of recurrence due to pathologic types, site of recurrence, disease free interval, detection method of recurrence, and also treatment and progression of recurrence. A patients in which the clinical examination was entirely negative and the $I^{131}$ scan demonstrated either a new area of $I^{131}$ uptake or an increased area of concentration, compared to the previous scan, was designated as a recurrence detected by $I^{131}$ scan only. Recurrences that were obviously by physical examination or chest x-ray, etc were considered clinically detected recurrence, regardless of the the results of the thyroid scan. Results: Mean of disease tree interval(DFI) is 36months. When mean DFI of $I^{131}$ scan detected recurrence is 28months, whereas mean DFI of clinically detected recurrence is 47months. In statiscal analysis, p-value is 0.043 as significantly. In progression of recurrent patient, NED is 28case, AWD is Sease, DOD is 13case. Among the 13case, scan detected recurrence is lease of 20 patients(5%), whereas clinically detected recurrence is l2case of 26 patient(46%). In statiscal analysis, p-value is 0.003 as significantly. Conclusion: Early detection of the recurrent thyroid cancer by $I^{131}$ scanning leads to good progress compare with detection by clinical examination. NED: No Evidence of Disease AWD : Alive With Disease DOD : Dead Of Disease DOC: Dead of Other Cause