Toxocariasis is a common zoonotic parasitic disease, primarily caused by the larvae of Toxocara canis or T. cati. Humans become infected through accidental ingestion of infective eggs in soil contaminated with feces of infected animals, or by consuming undercooked meat from paratenic hosts harboring Toxocara larvae. This cross-sectional study aimed to evaluate the seroprevalence of Toxocara spp. in 250 mothers and their 250 neonates referred to selected teaching hospitals affiliated with Shahid Beheshti University of Medical Sciences, Tehran, Iran in 2020. Data were recorded using a specialized questionnaire, and serum and peripheral blood smears (for eosinophil count) were collected. Serum samples were tested using the ELISA serological test for IgG antibodies against Toxocara spp. The collected data were analyzed using IBM SPSS Statistics software version 21.0. A chi-square test was performed, and a P value less than 0.05 was considered statistically significant. Among the 500 participants, 24 cases (4.8%) tested positive for anti-Toxocara canis IgG antibodies. Seropositive cases included 6 mothers only (25%), 6 neonates only (25%), and 12 cases both mother and their neonate (50%). Statistical analysis showed a significant relationship between the presence of anti-Toxocara antibodies and hospital type and nationality (P value < 0.05). However, no significant relationship was found between the presence of antibodies and other demographic variables such as age, sex, eosinophilia, and history of contact with animals in mothers and their neonates (P value > 0.05). This study indicates a substantial rate Toxocara infection in mothers and neonates, necessitating appropriate preventive measures by the relevant authorities.