Introduction: The differentiated thyroid cancer has generally an excellent prognosis after the treatment. The aim of this study is to describe the characteristics of persistent or recurrent differentiated thyroid cancers. Patients/ Methods: It is about a descriptive and retrospective study conducted from 392 patients followed for differentiated thyroid cancer. The data concerning the persistent or recurrent differentiated thyroid cancer have been collected from 1986 to 2015 in endocrinology service in Ibn Rochd CHU. Results: In total, twenty-four patients have shown the relapse or the persistency of their tumor, corresponding to the prevalence of 6.12 percent. The papillary carcinoma was dominant in 79 percent of cases and the follicular carcinoma in 21 percent of cases. The metastases were cerebral (two cases), lung (3 cases), bones (3 cases, Figure 1), and lymph nodes (9 cases). In our series, eighteen cases of persistent differentiated thyroid cancer have been found against six cases of recurrent differentiated thyroid cancer. Two cases of death at least three years of followed in our series and concerned the two cases of cerebral metastasis. Conclusion: The persistent or recurrent differentiated thyroid cancer rate is low in our series. The discovery of the relapse t is late.