This study aimed to investigate the epidemiology of canine ophthalmic diseases in Seoul, Korea using data for new canine patients examined from January 2009 through December 2013 at an ophthalmic referral center (WooSung Animal Medical Center, Seoul). The study included 1253 dogs with an average age of 7.93 years (SD, 4.06). Shih Tzu (29.4%) was the most common breed, followed by Maltese, Yorkshire Terrier, Cocker Spaniel, and toy Poodle (P < 0.01). Lens diseases (28.3%) were the most common, followed by eyelid, corneal, retinal, and glaucomatous diseases (P < 0.01). Lens, eyelid, retinal, nasolacrimal, uveal, vitreous, and neuro-ophthalmic diseases more frequently showed a bilateral occurrence (P < 0.01) than a unilateral occurrence. In the Shih Tzu breed, corneal disease was the most frequent, followed by lens, eyelid, retinal, and glaucomatous diseases. The most frequent diseases in the Maltese breed were lens, eyelid, retinal, and corneal diseases. In the Yorkshire Terrier, Cocker Spaniel, and toy Poodle breeds, lens disease was the most common (P < 0.01). The most frequent ophthalmic patients belonged to small breeds such as Shih Tzu, Maltese, and Yorkshire Terrier. Moreover, the most common ophthalmic diseases were not traumatic diseases, but breed-inherited diseases such as lens diseases.