A gas-insulated switchgear of a double bus bar system, comprising: a first bus bar; a second bus bar that is arranged below the first bus bar and is parallel to the first bus bar; a first bus-bar connection unit that is connected between face-to-face bus bar ends of the first bus bar and partitions the first bus bar; and a second bus-bar connection unit that is connected between face-to-face bus bar ends of the second bus bar and partitions the second bus bar, characterized in that the first bus-bar connection unit includes a first connection tank of a vertical shape that includes a branch outlet led out in a horizontal direction orthogonal to the first bus bar, where one of the bus bar ends of the first bus bar (1:) is connected to the branch outlet, a first circuit breaker of a vertical shape that is arranged in an upper portion of the first connection tank, and that includes a branch outlet on a side opposite to the branch outlet of the first connection tank, a first inclined connection tank that has a side surface of an upper end connected to the branch outlet of the first circuit breaker, that has a lower end arranged on a side of the other bus bar end of the first bus bar, and that is inclined with respect to the first connection tank, and a first connection bus bar that has one end connected to the lower end of the first inclined connection tank, that extends in a horizontal direction orthogonal to the first bus bar, and that has the other end connected to the other bus bar end of the first bus bar, and the second bus-bar connection unit includes a second connection tank of a vertical shape that is arranged to face the first connection tank across the first connection bus bar in an extending direction of the second bus bar, and that includes a branch outlet led out in a horizontal direction orthogonal to the second bus bar, where one of the bus bar ends of the second bus bar is connected to the branch outlet, a second circuit breaker of a vertical shape that is arranged in an upper portion of the second connection tank, and that includes a branch outlet on a side opposite to the branch outlet of the second connection tank, a second inclined connection tank that is longer than the first inclined connection tank, that has a side surface of an upper end connected to the branch outlet of the second circuit breaker, that has a lower end arranged below the lower end of the first inclined connection tank, and that is inclined in an opposite direction to an inclining direction of the first inclined connection tank, and a second connection bus bar that has one end connected to the lower end of the second inclined connection tank, that extends in parallel to the first connection bus bar, and that has the other end connected to the other bus bar end of the second bus bar. a first bus bar; a second bus bar that is arranged below the first bus bar and is parallel to the first bus bar; a first bus-bar connection unit that is connected between face-to-face bus bar ends of the first bus bar and partitions the first bus bar; and a second bus-bar connection unit that is connected between face-to-face bus bar ends of the second bus bar and partitions the second bus bar, characterized in that the first bus-bar connection unit includes a first connection tank of a vertical shape that includes a branch outlet led out in a horizontal direction orthogonal to the first bus bar, where one of the bus bar ends of the first bus bar (1:) is connected to the branch outlet, a first circuit breaker of a vertical shape that is arranged in an upper portion of the first connection tank, and that includes a branch outlet on a side opposite to the branch outlet of the first connection tank, a first inclined connection tank that has a side surface of an upper end connected to the branch outlet of the first circuit breaker, that has a lower end arranged on a side of the other bus bar end of the first bus bar, and that is inclined with respect to the first connection tank, and a first connection bus bar that has one end connected to the lower end of the first inclined connection tank, that extends in a horizontal direction orthogonal to the first bus bar, and that has the other end connected to the other bus bar end of the first bus bar, and the second bus-bar connection unit includes a second connection tank of a vertical shape that is arranged to face the first connection tank across the first connection bus bar in an extending direction of the second bus bar, and that includes a branch outlet led out in a horizontal direction orthogonal to the second bus bar, where one of the bus bar ends of the second bus bar is connected to the branch outlet, a second circuit breaker of a vertical shape that is arranged in an upper portion of the second connection tank, and that includes a branch outlet on a side opposite to the branch outlet of the second connection tank, a second inclined connection tank that is longer than the first inclined connection tank, that has a side surface of an upper end connected to the branch outlet of the second circuit breaker, that has a lower end arranged below the lower end of the first inclined connection tank, and that is inclined in an opposite direction to an inclining direction of the first inclined connection tank, and a second connection bus bar that has one end connected to the lower end of the second inclined connection tank, that extends in parallel to the first connection bus bar, and that has the other end connected to the other bus bar end of the second bus bar.