Background: Psychomotor development is the most important outcome determining the proper growth and development of children. Optimizing childcare and modifying risk factors can provide the child with the best conditions to realize their developmental potential. The study aimed to assess the impact of the feeding method on the psychomotor development of full-term children at 12 months of age with Munich Functional Developmental Diagnostics (MFDD). Methods: The study included 242 full-term children who were examined at 12 months of age by a child neurologist using MFDD. The children were divided into two groups depending on the feeding method: breastfed (146) vs. formula-fed (93). We analysed selected obstetric and neonatal risk factors as well as MFDD scores within the groups. Results: The only axis on the MFDD scale on which we observed a difference between the groups was social skills. No differences were noted between the groups in the analysis of the gross and fine motor skills, with regard to perception or active and passive speech. Conclusions: The full-term, exclusively breastfed infants over their first 6 months of age or longer have greater social skills in comparison with the formula-fed infants when measured on the MFDD axis.