A microphone unit (1, 2, 3, 6, 7, 8), comprising: a case having a first sound hole and a second sound hole formed on a surface of the case; a first vibrating part for converting a sound signal to an electrical signal on the basis of vibration of a first diaphragm; a second vibrating part for converting a sound signal to an electrical signal on the basis of vibration of a second diaphragm; a base and a substrate including a top surface on which the first vibrating part and the second vibrating part are installed; and a top lid placed over the top surface, the top lid covering the first and second vibrating parts (14, 15) and having formed therein the first sound hole and the second sound hole, wherein the first diaphragm has a first surface communicated with the first sound hole through a first sound channel formed in the case and a second surface facing a sealed space formed in the case; and the second diaphragm has a first surface communicated with the first sound hole through the first sound channel formed in the case and a second surface communicated with the second sound hole through a second sound channel formed in the case, characterized in that the first and second vibrating parts (14, 15) are installed on the substrate with the first and second diaphragms (142, 152) being disposed in parallel with the surface of the case having the first and second sound holes (132, 133), and the second sound channel is formed using the second sound hole, a second opening of the substrate, a hollow space, and a first opening of the substrate, wherein the hollow space is formed using a first groove part of the base and a bottom surface of the substrate, and the groove part has a substantial T shape or a substantial rectangular shape. a case having a first sound hole and a second sound hole formed on a surface of the case; a first vibrating part for converting a sound signal to an electrical signal on the basis of vibration of a first diaphragm; a second vibrating part for converting a sound signal to an electrical signal on the basis of vibration of a second diaphragm; a base and a substrate including a top surface on which the first vibrating part and the second vibrating part are installed; and a top lid placed over the top surface, the top lid covering the first and second vibrating parts (14, 15) and having formed therein the first sound hole and the second sound hole, wherein the first diaphragm has a first surface communicated with the first sound hole through a first sound channel formed in the case and a second surface facing a sealed space formed in the case; and the second diaphragm has a first surface communicated with the first sound hole through the first sound channel formed in the case and a second surface communicated with the second sound hole through a second sound channel formed in the case, characterized in that the first and second vibrating parts (14, 15) are installed on the substrate with the first and second diaphragms (142, 152) being disposed in parallel with the surface of the case having the first and second sound holes (132, 133), and the second sound channel is formed using the second sound hole, a second opening of the substrate, a hollow space, and a first opening of the substrate, wherein the hollow space is formed using a first groove part of the base and a bottom surface of the substrate, and the groove part has a substantial T shape or a substantial rectangular shape.