Thyroglossal duct cysts (TGDCs) are congenital and developmental abnormalities in infants and young children. This retrospective case series study examined the characteristics of 7 patients <3 years (mean age, 1.9 years) with TGDC complicated with a parapharyngeal mass treated at one hospital between January 2019 and 2022. Four patients had a painless mass around the neck, 2 had a painless mass associated with snoring, and 1 presented repeated swelling and pain. B-ultrasound suggested 6 cases of TGDC and 1 possible lymphangioma. All patients were treated with Sistrunk surgery to remove the TGDC. Six patients had no cyst recurrence during follow-up (6 months to 2 years). In conclusion, TGDC complicated with a parapharyngeal mass has complex and variable clinical manifestations. Completely removing the cyst while sparing thyroid cartilage and surrounding vascular and neuroanatomical structures is important to avoid complications. The patients are likely to be free from recurrence after surgery.