There are controversies on the benefits of elective neck dissection (END) for clinically negative neck in early stage oral squamous cell carcinoma. The aim of this study is to determine the need for a randomized controlled trial in order to evaluate the survival benefit of elective neck dissection on the prognosis of T1, 2 N0M0 patients with carcinoma of oral cavity. We initiate this multi-institutional study, expecting 448 primary oral cancer patients to be enrolled. And we are going to randomly divide these patients into two groups: END and "watch and wait". The END group will undergo one stage surgery of END and primary tumor excision, and the "watch and wait"group will be treated with primary tumor excision transorally as initial treatment, with rigorous postoperation consultation. All patients will be followed up with at least 5 years after initial treatment, and the survival rate and the recurrence rate between groups will be compared.