This investigation was performed to detect the seroprevalence of Toxocara canis in humans by ELISA and distribution of intestinal parasites in dogs in Van province. The study was carried out between 2005-2007 Septembers. Eight hundred patients with complaints such as abdominal pain, hypereosinophilia and urticaria who were inspected in various outpatients' clinics of the Research Hospital of Yuzuncu Yil University and 100 healthy individuals as control group were investigated. T. canis seropositivity by ELISA, eosinophil counts and total IgE levels were investigated in blood samples received from patients and control group individuals; stool samples of persons were also examined with native-Lugol, trichrome staining and formalin-ether sedimentation methods. Besides, the stool samples of 420 dogs were also taken for the investigation of intestinal parasites. The stools of the dogs were examined for T canis and other intestinal parasites macroscopically, by native-Lugol, modified acid-fast staining and flotation methods. It was detected toxocariasis seropositivity in 15.25% and intestinal parasites in 13.88% of human. It was determined the eosinophilia in 25% of patients and toxocariasis seropositive in 28.05% of these patients. It was detected urticaria in 32.78%, pruritus in 22.13% and abdominal pain in 9.83% of patients with toxocariasis. One or more intestinal parasites were founded in 63.10% of the dogs, and T. canis was encountered as 19.05%. Positive relationship was detected among toxocariasis and living in rural area (P<0.01), eosinophilia (P<0.001), ageing (P<0.001) and high level of IgE (P<0.001). It was concluded that, toxocariasis is frequently encountered in humans and animals in Van province, measures should be taken to prevent this disease and ELISA method should be take place between routine diagnostic tests for diagnosis of this disease in human.