A system and a method for measuring an ash content and a calorific value of a coal are provided. The system comprises: an X ray device, disposed over the coal and configured to emit an X ray to the coal; at least one X ray measuring device, disposed over the coal and configured to measure an energy spectrum of an X ray reflected by the coal; a distance sensor, disposed over the coal and configured to measure a distance between the coal and the at least one X ray measuring device; and a computing device, configured to receive the energy spectrum and the distance from the at least one X ray measuring device and the distance sensor and to compute the ash content and the calorific value of the coal according to the energy spectrum and the distance.