In view of the confusion about the concept, classification and diagnostic terminology of dermatitis and eczematous diseases, the Immunology Group of Chinese Society of Dermatology and the Guideline Formulation and Standardization Committee of China Dermatologist Association organized experts to discuss current status and existing problems of diagnosis of dermatitis and eczematous diseases according to the Delphi method. Seven suggestions on standardized diagnosis were put forward, mainly including: (1) "dermatitis" and "eczema" are the category names of diseases rather than specific diagnostic terms; (2) when eczematous skin lesions are encountered clinically, doctors should actively look for relevant clinical and/or laboratory characteristics, and classify and diagnose them according to the terms or categories atopic dermatitis, contact dermatitis and other dermatitis; (3) the term "eczema" is recommended to be retained at present, and can only serve as a temporary and descriptive diagnostic term for eczematous skin lesions which cannot be definitely diagnosed for the time being. This consensus aims to promote the standardization and homogenization of diagnostic terms for dermatitis and eczematous diseases, and lay a foundation for improving disease management, epidemiological research and individualized treatment and prevention.