The utility model relates to an insulating tube provided with an internal screening. The insulating tube comprises an insulating tube, a connecting supporting stand and a transformer chassis, wherein an internal screening ring is arranged on the insulating tube, and the internal screening ring is fixedly connected on the transformer chassis through the connecting supporting stand. The insulating tube conducts screening protection to the sharp end of device bodies, thereby improving the discharge of the device bodies, and leading the local discharge of the transformer to be small, the local discharge effect of products is better, and further reaches requirements of plants, electric fields distribution is improved, and local discharge is excellently controlled.