Abstract: Basing upon histopathological studies of 21 cases of rosacea, the relation between mite infection and pathological changes in the parasitized tissues was correlated.Many mites were found in the dilated hair follicles or proliferative sebaceous glands, particularly in lesions associated with varying grades of inflammatory reaction. Results showed that the histopathological changes are intimately in correlation with the infection of two species of human hair follicles mites in patients of 3 forms of rosacea. These suggest that human hair follicle mites are pathogenic, and can be the important causative agents of dermatitis form of rosacea. Both species of mites (Demodex folliculorum and Demodex brevis) are related to the etiolology of acne and rhinophyma forms of rosacea. It gives support to the clinical diagnosis and treatment of rosacea.