The invention discloses a cable integrated connecting device with the characteristic of convenient maintenance and a connecting method thereof. The connecting device comprises a left connecting devicebody and placing slots. A telescopic frame is installed at the right side of the left connecting device body; a right connecting device body is fixed at the right side of the telescopic frame; firstthrough holes are formed inside the left connecting device body; second through holes are formed in the left side and the right side of the first through holes; support rods are fixed at the outer sides of the second through holes; and fixed nuts are installed at the outer sides of the support rods. Fixed suction disks are arranged at the bottoms of the support rods; and a left cover body is installed above one support rod. According to the integrated connecting device, with clamping plates and magnet blocks, the arc clamping plates and magnetic fixed slots are absorbed and fixed by the magnetblocks, so that connected cables in the placing slots are fixed by the clamping plates and thus connector is protected from being affected by cable shaking and the cable can work stably.