A multi-level boost apparatus. Voltage allocation among N first switches is achieved by connecting N voltage dividing modules, sequentially connected in series, in parallel with the N first voltage switches, respectively. Thereby, a voltage across each of the N first switches is within a safety range. Even if an input voltage is high and a voltage across a flying capacitor is zero at an instant of being powered, it is prevented that a second one to an N-th one of the N first switches break down due to overvoltage.