On an improved DC planar magnetron sputtering system using a solenoid coil outside a pyrex glass chamber, the magnetic field distributions near the target surface and DC discharge characteristics are investigated for various solenoid coil currents. As the improved magnetron system is symmetric with respect to the center pole, the measuring area of magnetic field distribution is two-dimensional plane. Sputtering is carried out at the pressure of 0.083 Pa of pure argon or nitrogen gas. Ti disk is used as a target. As a solenoid coil current which flowing direction is suitably chosen increases from 1 to 4 A (DC), the parallel component of magnetic field to the target surface and DC discharge current increase, but both DC discharge voltage and sparking voltage decrease. And DC discharge voltage and sparking voltage in an atomosphere of argon gas are smaller than that in nitrogen gas.