Radioactive iodine (RAI) is commonly used postoperatively for differentiated thyroid carcinoma remnant ablation or metastasis. However, literature regarding the time of use lacks. Therefore, this meta-analysis assessed the same. The authors searched PubMed, Cochrane Library, and Google Scholar for references comparing early and late radioactive iodine administration among patients with differentiated thyroid carcinoma. The keywords used were early, late, radioactive iodine, outcomes, disease free survival, response to therapy, survival rates, remnant ablation, differentiated thyroid carcinoma with the Protean "AN" and "OR". Among the 515 titles identified through abstracts and references, 256 articles were eligible, of them ten full texts fulfilled the inclusion and exclusion criteria. Depending on the cut-off period after which RAI therapy is regarded as late we have seven articles with cut-off period= three months and three with a six months period. The studies included 50736 patients and 28418 events, no differences in the outcomes between early and late RAI administration were found when considering ether three months or six months as a cut-off. (P-values=0.22 and 0.61 respectively). However, a substantial heterogeneity was observes, I2, 75% and 82%, Chi-square, 24.34, and 10.82 respectively, and P-values for heterogeneity, < 0.001 and 0.004 respectively. A sub-analysis showed that our results remained robot even after illuminating the studies with considerable heterogeneity (P-value=0.56, P-value for heterogeneity, 0.49, I2=0, Chi-square, 3.41, and mean difference, 4.). Radioactive iodine can be delayed up to six months after surgery paying the time according to the local facilities and the patient's characters.