The Robin sequence, previously known as the Pierre Robin syndrome, is characterized by the sequence of clinical events that result from a small mandible.The tongue becomes posteriorly displaced (glossoptosis) and obstructs the airway.Patients with Robin sequence may also present with a cleft palate, although this is not necessary to make the diagnosis.The obstructing tongue also makes oral feeding difficult and, in severe cases, impossible.What were mandibular deficiency?how evaluate?therefore, the diagnosis have three question.the first is how to decide small mandible.the second is how to deride obstructs the airways.The third is what is the diagnosis standard.We had intervened 686 Robin sequence cases and research the group of cases.We think diagnostic criteria of Robin sequence is indistinct.our diagnostic criteria were:lClinical Features:First is Classic triads,U-shaped cleft palate,Micrognathia/retrognathia, Glossoptosis (observed tendency of the tongue to move posteriorly obstructing the oropharynx)2: mandibular deficiency:the second is mandibular deficiency and upper airway obstruction.3: respiratory difficulty:.The third is respiratory difficulty,such as often the first sign causing concern relating to feeding.Accord with the above two can diagnosis Robin sequence.Indications for surgerv:a.UDDer airway obstruction and apnea.oxyhemoglobin saturation<90%.