Dirofilariasis was reported among imported German Shepherd dogs in Assiut Governorate, Upper Egypt. Microfilariae of D. immitis were detected in blood films of 8 out of 19 examined dogs, constituting a total 121 Assiut Vet. Med. J. Vol. 40 No. 79. October 1998 filarial incidence of 42.1%. Six of them were clinically ill and the other two dogs were asymptotically infected. All clinically diseased dogs were tired, even collapsed, after mild exercise. Severe debility, vomiation and cough were noticed also in three of them which were suffering from skin and ocular lesions. Blood of all infected dogs had a high eosinophilia ranged from 22 to 36 %. Stray infested dogs are incriminated as a source of infection to the imported non-infested dogs. We suggested the transmission of D. immitis by local mosquito vectors which were found in high population in areas near to the River Nile especially in summer season. The present study concluded that all imported dogs of foreign breeds into Egypt should be housed in insects proof houses especially at night and should be given annually a prophylactic doses of antifilarial compounds.