In recent years, with the improvement of the sensitivity of examination equipment and the change of people's living environment and diet, the rate of thyroid cancer has risen rapidly, which has increased nearly five folds in 10 years. The pathogenesis, clinical manifestation, biological behavior, treatment and prognosis of thyroid carcinoma of different pathological types are obviously different. Papillary thyroid carcinoma (PTC) can develop at any age, which accounts for about 90% of thyroid cancer. It progresses slowly and has favourable prognosis, but lymph node metastasis appears easily. Whether PTC is accompanied by lymph node metastasis has an important impact on its prognosis and outcome. The Raf murine sarcoma viral oncogene homolog B(BRAF)gene mutation plays a crucial role in PTC lymph node metastasis. Having an in-depth understanding of the specific role and mechanism of BRAF gene mutation in PTC is expected to provide new ideas for diagnosis and treatment of PTC.