LINC00894 plays an important role in cancer cell proliferation and invasion in breast and kidney cancer. However, its role in thyroid cancer proliferation and metastasis remains unclear. In this study, data on LINC00894 expression in thyroid cancer tissues were obtained from GEPIA2. miRNA expression in thyroid cancer tissues was obtained from starBase 3.0 and OncomiR. Cell proliferation was evaluated using CCK-8, and Transwell chambers were used for the migration and invasion assays. LINC00894 and let-7e-5p expressions in thyroid cancer cells were measured using qRT–PCR. Meanwhile, TIA-1 expression in thyroid cancer cells was analyzed via western blotting. We found that LINC00894 expression was markedly reduced in thyroid cancer tissues and cells, and low expression of LINC00894 was associated with poor prognosis in thyroid cancer. LINC00894 overexpression inhibited the proliferation, migration, and invasion of CAL-62 and TPC-1 cells. Additionally, let-7e-5p expression was substantially enhanced in CAL-62 and TPC-1 cells. LINC00894 overexpression promoted TIA-1 expression by acting as a sponge of let-7e-5p. Finally, let-7e-5p weakened the function of LINC00894 in thyroid cancer cells via reduction in TIA-1 levels. In conclusion, our data suggest that increased LINC00894 expression reduces the oncogenic properties of thyroid cancer cells by sponging let-7e-5p to promote TIA-1 expression.