Abstract: The present invention discloses a magnetic filter tube, and relates to the technical field of magnetic filters. The magnetic filter tube includes a first rectangular tube and a second rectangular tube, where one end of the first rectangular tube is fixedly connected to one end of the second rectangular tube; the other end of the first rectangular tube forms an inlet of the magnetic filter tube; the inlet of the magnetic filter tube is connected with a cathode target flange; the other end of the second rectangular tube forms an outlet of the magnetic filter tube; the outlet of the magnetic filter tube is connected with a vacuum chamber; an inner wall of the first rectangular tube and an inner wall of the second rectangular tube are each provided with a protrusion and a groove; the protrusion is filled with cold water.