A unified scheme of index control based on big data platform is proposed due to the inadequacy of the traditional index control of grid operation and management. In the scheme, a unified index control system of grid operation and management is proposed. Using the massive data of power grid operation and dispatch management and the high-efficient capacity of data analyzing and processing supplied by big data platform, the data fusion and sharing of multi-stage control center and multi-specialty is implemented. Using index system definition tool, the user-defined function of index calculation formula is implemented. Using index calculation engine and task scheduling technology, the function of index automatic calculation is realized. The scheme has been applied as a pilot in the control center. Practice shows that it can solve the inadequacy of the traditional index control and totally improve the grid fine operation and management level.