The river sand was replaced by waste cathode ray tube（CRT）glass to prepare green ultra high performance concrete(UHPC). The effect of waste CRT glass on the flowability, mechanical strength and bending performance of UHPC was investigated. The microstructure of UHPC was studied. The results show that the incorporation of waste CRT glass increases the flowability and reduces the mechanical strength and energy absorption capacity of UHPC. The reduction degree of properties indexes is less than 5 % when the replacement ratio of waste CRT glass is below 25%. The CRT glass restrains cement hydration. The addition of CRT glass also reduces the performance of interfacial transition zone in UHPC, which leads to the decreased mechanical strength.