Limits to the amount and quality of fly ash as mineral additive of concrete in current specifications are mostly very restricted in China. A case history and studies by presented, however, have shown that, high strength and excellent durability could be obtained for the concrete with high volume of fly ash. Based on the discussion about this difference in behavior between fly ash and Portland cement under low ratio of water to cementitious the performance of bulk concrete and the relation between temperature rise and strength can be significantly improved. A conclusion is reached: fly ash is an important resource to develop green HPC(for concrete to become a sustainable construction material) and it should be considered as an independent constituent for concrete materials.