A boost converter includes a first boost conversion unit and a second boost conversion unit. Coils of the first boost conversion unit and the second boost conversion unit are coupled with each other. Due to coupling of the coils, the second boost conversion unit releases energy while the first boost conversion unit stores energy in a period of time. Furthermore, due to coupling of the coils, the first boost conversion unit releases energy while the second boost conversion unit stores energy in another period of time. The two boost conversion units operate alternately, thereby adjusting switching loss and averaging output power of components. Furthermore, as switching frequency increases, the coil inductance, as well as the capacitance required in the two boost conversion units can be reduced correspondingly, thus substantially enhancing responses of the two boost conversion units as a whole.