Background: Parapharyngeal space tumor is a tumor that occurs in the parapharyngeal space. Parapharyngeal space tumors are uncommon, accounting for about 0.5% of head and neck tumors. Eighty percent of them are benign and 20% are malignant. The pathologic types of tumors are varied, mainly neurogenic tumors and salivary gland tumors. Follicular dendritic sarcomas are much rarer, with an inert biological behavior and a low-grade malignant sarcoma. Clinicians face difficulties in the management of this lesion. Therefore, a comprehensive analysis of the management of this disease is necessary. Case presentations: In May 2023, a 22-year-old male presented with pharyngeal discomfort, dysphagia, and sleep apnea. The patient underwent MRI which showed a rounded hypodense shadow with a size of 3.2×2.1×4.5 cm in the left lateral pharyngeal wall and a mass located in the posterior aspect of the left submandibular gland. After preliminary diagnosis of left parapharyngeal space tumor and left neck mass, the clinician performed transoral endoscopy-assisted resection of the left parapharyngeal space tumor and transcervical resection of the left cervical mass. The patient has been followed up without recurrence. Conclusions: This case provided a reference for the diagnosis and management of parapharyngeal space tumors. In particular, new insights into the diagnosis and management of a rare pathologic type were presented, which had the potential to improve the overall understanding of this disease.