The present disclosure provides an endotracheal tube retainer for retaining an endotracheal tube. The endotracheal tube retainer has a clip to be supported on a head such that the clip is spaced apart in front of a mouth and is adjustable between an open configuration and a closed configuration. In the closed configuration, the clip defines a tube retention channel that may receive the endotracheal tube such that the clip grips the endotracheal tube to retain it in the clip. The open configuration releases the endotracheal tube such that the endotracheal tube is movable relative to the clip. The clip can be equipped with primary and secondary retention features for holding the clip closed. The clip can be opened and closed by one-handed operation. The retainer has a stabilizer extension used for stabilizing the endotracheal tube during one-handed operation of the clip.