A connection device includes a first braided conductor having a tubular shape, and a second braided conductor having a tubular shape. The connection device also includes a tubular member having a first opening end and a second opening end, and the tubular member having conductivity. A first annular member fixed to the first opening end in a state that the first braided conductor is sandwiched coaxially between the first annular member and an outer peripheral surface of the first opening end. A second annular member fixed to the second opening end in a state that the second braided conductor is sandwiched coaxially between the second annular member and an outer peripheral surface of the second opening end. The first braided conductor and the second braided conductor are conductively connected to each other through the tubular member.