To evaluate the Toxocara spp. eggs environmental contamination of the soil of the urban or suburban area Ancona (Italy), 22 public playgrounds were selected and several cores of soil were taken from any selected areas. To study the Toxocara seroprevalence in the inhabitants of Ancona, blood samples were collected from selected groups of individuals. One hundred and sixty-three blood samples were tested using an enzyme linked immunosorbent assay (ELISA) technique (Lofarma Lab, Milan, Italy) for the detection of IgG-specific antibodies to T. canis excretory-secretory antigens. Toxocara spp. eggs were found in the soil samples from 14 (63.6%) playgrounds. Toxocara seroprevalence was detected in blood specimens from six (8.1%) out of 74 symptomatic individuals and from one (1.1%) out of 89 asymptomatic controls. Among symptomatic individuals, the association between Toxocara seroprevalence and eosinophilia resulted statistically significant (p = 0.029). The high environmental contamination frequency found make necessary to prompt preventive public health measures, such as control of stray animals, treatment of infected pets and hygiene education of the population.