Human toxocarosis is an important parasitic zoonosis caused by larval stages of Toxocara species, the roundworms from dogs and cats. Larval migration through different soft tissues in the human generates several clinical entities in the patient, such as visceral larva migrans, ocular toxocarosis, and neurotoxocarosis. Definitive diagnosis by histopathological methods is very difficult or almost impossible and, nowadays, the diagnosis is usually made by clinical signs/symptoms, epidemiological background of the patient and the use of hematological and immunological tests which finally help to confirm the clinical suspicion of the illness. The purpose of this paper was to update the available knowledge on the use of different tools for both the diagnosis and following up of human toxocarosis.