Sialoblastoma should be considered in the diagnosis of a perinatal neck swelling that appears to be contiguous with the submandibular salivary gland. These are exceedingly rare perinatal salivary tumors of epithelial origin with variable biologic behavior including the potential for local and systemic recurrence. We report the case of a 3-month-old boy who presented with a submandibular swelling of insidious onset that was initially thought to be a lymph node enlargement.