The invention discloses an oil storage tank guide pillar sealing insulating device comprising a metal floating disc. The center of the metal floating disc is provided with an opening, a guide pillar is inserted into the opening, and the diameter of the opening is larger than that of the guide pillar. The guide pillar is sleeved with a rubber ring, and the guide pillar and the inner side wall of the rubber ring are in sliding sealing connection. The rubber ring is located on the metal floating disc, the outer side of the rubber ring is provided with a fixing barrel, and the bottom of the fixingbarrel is fixedly connected with the metal floating disc. By rotating handles, pressing plates slide downwards on the inner side wall of the fixing barrel so that the rubber ring can be tightly clamped; the bottom of the rubber ring is provided with a plurality of occlusion teeth, and the occlusion teeth are inclined and have elasticity; and when the occlusion teeth are clamped in occlusion slotsformed in the metal floating disc, the rubber ring can be prevented from rotating, the metal floating disc cannot be in direct contact with the guide pillar, the phenomenon of spark discharge can beavoided, and potential safety hazards are avoided.