A circuit and a method for powering a single-chip microcomputer by transient electric energy. The circuit comprises a single-chip microcomputer (U2), a piezoelectric ceramic power generation device (J1), a transient electric energy acquisition circuit and multiple energy storage capacitors (C1 to C18). The piezoelectric ceramic power generation device (J1) is connected to the single-chip microcomputer (U2) by the transient electric energy acquisition circuit, and multiple IOs of the single-chip microcomputer (U2) are connected to a power ground GND by the energy storage capacitors (C11 to C18), respectively. The method comprises converting transient electric energy to magnetic energy, and converting the magnetic energy to electric energy for powering the single-chip microcomputer (U2). By using a maximum power tracking method, power voltage of the single-chip microcomputer (U2) is tracked, and charging and discharging of the energy storage capacitors (C11 to C18) is controlled, such that the single-chip microcomputer (U2) in operation is at maximum power. The single-chip microcomputer (U2) is powered by transient electric energy acquired by the transient electric energy acquisition circuit, the energy storage capacitors (C11 to C18) are additionally connected to the IOs of the single-chip microcomputer (U2), and charging and discharging of the energy storage capacitors (C11 to C18) is controlled, ensuring power and voltage is sufficient for normal operations of the single-chip microcomputer (U2).