In this paper,two cases of cyst of temporomandibular joint were reported.We studied eleven cases' literature combined with our clinical and pathological findings,including B typed ultrasonography, CT image and surgical management.We analyzed this kind of cyst from etiological pathological and clinical features and diagnostic therapeutic event.It is a very rare disease with the preferential incidence in woman.We suggested B typed supersonic exam be the first exam method,surgical removal is the best regime.But final diagnosis is depend upon biopsy.