The invention discloses a method for vertical shaft electric-heating-assisted depressurizing production of a natural gas hydrate reservoir. An electrode is mounted at the lower end of an oil pipe mainly, in combination with depressurizing production of natural gas hydrates, current is forced to pass through the natural gas hydrate reservoir, a current loop is formed, thermal production of the natural gas hydrates is realized, and the recovery ratio of the natural gas hydrate reservoir is increased. The specific method comprises steps as follows: the electrode is mounted at the lower end of the oil pipe, ground electric power adjusting equipment transmits the current to the downhole electrode through a cable, the natural gas hydrates are partially decomposed through depressurizing production, water produced through decomposition of the natural gas hydrates is used as an electric conductor and the natural gas hydrate reservoir is used as a resistor for heating, and thermal production of the natural gas hydrates is realized. The method is simple in structure, energy-saving, environment-friendly and easy to control, and an effective measure is provided for development of the natural gas hydrate reservoir.