Abstract Papillary thyroid carcinoma (PTC) is an aggressive histological subtype of thyroid carcinoma (THCA), whose occurrence rate is high. The participation of long noncoding RNAs in the pathologies of cancers has attracted significant attention during the past decades. The purpose of the current study is to investigate the role of NR2F1 antisense RNA 1 (NR2F1‐AS1) in PTC. The expression of NR2F1 in THCA samples was analyzed by bioinformatics tool gene expression profiling interactive analysis. Levels of NR2F1‐AS1, microRNA‐423‐5p (miR‐423‐5p), and SRY‐box 12 (SOX12) were evaluated by a quantitative reverse transcription‐polymerase chain reaction and Western blot. The impact of NR2F1‐AS1 on PTC cell proliferation and invasion was assessed by Cell Counting Kit‐8, EdU, and Transwell invasion assays. The interactions among NR2F1‐AS1, miR‐423‐5p, and SOX12 were determined by RNA immunoprecipitation and luciferase reporter assays. Consequently, we found that NR2F1‐AS1 and SOX12 levels were elevated in PTC, whereas miR‐423‐5p was downregulated in PTC cells. Functionally, NR2F1‐AS1 silence led to reduced proliferation and invasion of PTC cells. Mechanistically, NR2F1‐AS1 interacted with miR‐423‐5p to induce SOX12 expression in PTC cells. In conclusion, the present study firstly stated that NR2F1‐AS1 regulated miR‐423‐5p/SOX12 to promote proliferation and invasion of PTC, indicating NR2F1‐AS1 as a potential novel target for the molecular‐targeted therapy of PTC.