(A). Genetic factors: Certain types of eczema and is closely related with genetic.

(B). Environmental Factors
Many studies have confirmed that environmental factors are some major reasons for the increased prevalence of eczema. Environmental factors mainly refers to the growing number and complexity of environmental allergens, which include:
1. Synthetic fabrics, leather goods, and clothing related to bleach and dyeing agent, brightener, moth agents, antifungal agents.
2. Man-made foods, convenience foods, fertilizers, pesticides, artificial feed, feed additives, preservatives used in food processing, mining oxidants, flavors, colors, ripening agents, thickeners, etc.
3. Electromagnetic radiation, artificial building components, chemical coatings, plastics, rubber, synthetic fibers, adhesives, waterproofing agents, home and office electronic equipment, etc.
4. The chemical fuel combustion gases generated by the manufacturing environment of automobiles, boats, aircraft materials, asphalt roads, roadside green plant pollen and other allergens modern transportation.
5. Environmental allergens with modern lifestyle, such as the use of cosmetics and cats, parrots and so on.

(C). Infection factors
These organisms include Staphylococcus aureus, Malassezia, air-borne fungi such as Alternaria mold, Aspergillus, Fusarium, Penicillium chrysogenum, Aspergillus niger and Rhizopus nigricans, etc. It is based mainly in three aspects:
1. Some patients with eczema lesions microbial detection rate is higher.
2. Skin microbes have a pathogenic role for some eczema. Researchers have reported that lesions among the patients with atopic dermatitis and eczema, the overall detection rate of Staphylococcus aureus comes to 31.6%, and the total bacterial detection rate reaches 70.6%.

(D) dietary factors
Animals, minerals, foods with saccharin, acetic acid, citric acid, flavors, synthetic dyes. These foods can cause food allergy, eczema causing generation.

(E) drug factors
Generally drugs have caused any possibility of eruption of eczema

(F) other factors
Eczema can still be generated by a depression, fatigue, depression, anxiety, nervousness, agitation, insomnia and other neuropsychiatric factors and sunlight, ultraviolet light, cold, wet, dry, friction climate, caused by physical factors.