A method of manufacturing a microphone includes preparing a substrate and forming an oxide layer pattern on the substrate and an oxide layer on a rear side of the substrate. The vibration membrane is formed over the substrate by injecting conductive ions into the substrate. A sacrificial layer and a fixed electrode are sequentially formed on the substrate and the vibration membrane by removing the oxide layer pattern. A first photoresist layer pattern is formed on the fixed electrode, and an air inlet is formed by patterning the fixed electrode. A second photoresist layer pattern is formed on a rear side of the oxide layer, and a penetration hole, through which a portion of the vibration membrane is exposed, is formed by etching the oxide layer and the rear side of the substrate. An air layer is formed between the fixed electrode and the vibration membrane.