A 41-year-old woman with an enlarged right supraclavicular lymph node underwent a fine-needle biopsy, which confirmed the presence of metastatic squamous cell carcinoma. To identify the primary tumor, an 18F-FDG PET/CT scan was performed, revealing multiple metabolically active lymph nodes throughout the body, but no primary lesion was identified. Subsequently, an 18F-AlF-NOTA-FAPI-04 PET/CT scan was conducted, which demonstrated increased abnormal uptake in the cervix and revealed additional metabolically active lymph nodes. Thus, a biopsy of the uterine cervical region was performed, and the results confirmed cervical squamous cell carcinoma.