Two cases of plunging ranula are reported. Treatment consisted of the total removal of the sublingual gland and evacuation of the cystic contents by the intraoral approach. The cyst remained just after the surgery in both cases, but then gradually regressed and disappeared within two months after the surgery. These findings support total removal of the sublingual gland as being the best method of treatment. We believe that complete dissection of the cyst with cervical incision as well as drainage of the cystic contents are unnecessary when the diagnosis of the plunging ranula is confirmed.