The scientific data literacy competency index system is an important basis for evaluating the ability of scientific researchers to manage and utilize data for scientific research and innovation. It is an important premise and basis for analyzing the status quo of scientific data literacy education and analyzing data literacy education strategies and mechanisms. Based on the principles of science, orientation, operability, independence,flexibility, foresight, and sustainability, this paper established the scientific data literacy competency index system, and put forward 18 first-level indexes and 47 second-level indexes from three dimensions of "individual", "team" and "data ecology"(ITE for short). It also described and characterized each index content from three levels: "knowledge", "skill", and "attitude"(KSA for short). The index system based on ITE-KSA presents a multidimensional structure, which has both vertical category and capability domain hierarchy, as well as horizontal specific capacity factor decomposition. This makes the scientific data literacy competency index system very practical and operable in guiding the evaluation of scientific data literacy, related curriculum development and educational practice.