Oral lichen planus (OLP) is a common chronic inflammatory disease of oral mucosa. The diagnostic criteria of OLP is the cornerstone of clinical diagnosis and treatment and scientific research. However, there are various understandings of the diagnostic criteria in China. Thus several questions need to be answered, for example, how to combine the international diagnostic criteria with China's specific conditions, how to apply the criteria into clinical practice, and how to use the criteria guiding clinical work and scientific research in China. The authors of this article systematically introduced and discussed the development, content and difference of the international diagnostic criteria of OLP. We proposed "23 Princeples" for the selection of biopsy indications in OLP diagnosis based on authors' personal experiences in clinical and basic research and the actual conditions of Chinese clinicians. We also express our own views and suggestions about some other hot issues associated with OLP diagnosis.
口腔扁平苔藓（oral lichen planus，OLP）是一种常见的口腔黏膜慢性炎性疾病，其诊断标准是临床诊治和科学研究的基石，但目前对诊断标准的认识并不统一，特别是国际的诊断标准如何与我国具体国情结合，应用于临床，指导我国的临床工作和科学研究，这些问题亟待解决。本文对国际上OLP诊断标准的发展、内容特点、差异度等进行系统介绍和讨论，并结合切身临床和研究经验以及我国临床医师的具体实际，提出OLP诊断中活检适应证选择的"23原则"，并对其他与OLP诊断相关的热点问题提出建议。.
Keywords: Diagnostic criteria; Evaluation; Lichen planus, oral.