The invention provides a capacitive pressure sensor and a manufacturing method thereof. The capacitive pressure sensor comprises an insulating substrate; a lower electrode formed on the insulating substrate; and a semiconductor substrate with a groove formed on a first surface. The first surface of the semiconductor substrate is opposed to the lower electrode and bonded to the insulating substrate. The lower electrode is accommodated inside the groove. A gap is present between the lower electrode and the semiconductor substrate. The capacitive pressure sensor further comprises an upper electrode being a doped region formed in the semiconductor substrate corresponding to the groove; and an upper electrode lead wire and a lower electrode lead wire respectively connected to the upper electrode and the lower electrode. By making the upper electrode and the lower electrode respectively formed on the semiconductor substrate and the insulating substrate, the capacitive pressure sensor requires no use of expensive TSV technologies for isolation. By means of the technical scheme provided in the invention, technically complex deep-pit etching can be prevented. Capacitive characteristics can be further prevented from being affected by etching.