The purpose of this study is to investigate the prevalent allergens causing canine atopic dermatitis in Daejeon area. Twenty two dogs were diagnosed with atopic dermatitis by an using intradermal skin test (IDST). Allergens used for the IDST included 33 allergen extracts from nine allergen groups: house dust mites (HDM), house dust, moulds, trees, weeds, grasses, insects/fleas, epithelia and others. The 22 purebred dogs with atopic dermatitis enrolled in this study included Shi-tzus (10/22, 45.5%), Yorkshire terriers (5/22, 22.7%), Miniature pinschers (4/22, 18.2%), Pugs (2/ 22, 9.1 %) and Cocker spaniels (1/22, 4.5%). The age of onset of atopic dermatitis ranged from 5 months to 5 years old (median: 1.79 years). The males (12/22, 54.5%) and females (10/22, 45.5%) were almost equal. The number of positive reactions to allergens recorded in each dog with atopic dermatitis was 3 (9/22, 40.9%), 2 (8/22, 36.4%), 1 (3/ 22, 13.6%) and 4 (2/22, 9.1 %), respectively. The most common positive allergen reaction was HDM (52.6%). The other positive allergen reactions recorded were from house dust (17.5%), insects/fleas (15.8%), trees (5.3%), moulds (3.5%), kapok (3.5%), silk (3.5%), epithelia (1.8%), weeds (0%) and grasses (0%), respectively. Positive reactions recorded to Dermatophagoides farinae and D. pteronyssinus were in 53.3% and 46.7%, respectively. The IDST results demonstrate that the most common causative allergens in canine atopic dermatitis in Daejeon area were HDM.