The utility model provides a grading ring in an ultra-high voltage transmission line. The grading ring is applied to a transmission line formed by insulator strings, a link plate and a power transmission conducting wire sequentially connected; the grading ring comprising at least two annulets is fixed on the transmission line; the ring surfaces of at least two annulets form a hollow area used for accommodating the high-voltage ends of the two layers of insulator strings; and the normal direction of the ring surfaces of the annulets is perpendicular to the axial direction of the insulator strings. In the grading ring provided by the utility model, the multi-ring-shaped grading ring is circled at the circumference of the high-voltage ends of the insulator strings, so as to produce a better pressure equalizing effect to all high-voltage ends of the insulator strings. Compared with the prior art, especially for insulator strings with more than three layers, the grading ring reduces the rate of the high-voltage end of one insulator string being burnt out due to imbalanced voltage due to the fact of not being covered by the grading ring.