We present the case of a 36-year-old woman who works as a kindergarten teacher, often she is kneeling on her knees due to the nature of the job. Since a year ago, she noticed that her right knee was swelling. She had an orthopaedic examination when she could no longer bend her knee. Inspection and palpation revealed the swelling of the anterior and anterior-lateral aspect of the knee. MRI imaging revealed a large, sharply defined, lobulated lesion of the infrapatellar fat pad. After the surgical incision, a lobular lesion was found and surgically removed. Histological analysis confirmed a ganglion cyst.