Abstract: The 3D cipher is a new block cipher proposed in CANS 2008. The design principles of 3D are built on the AES, but it is different from the other known block cipher as it uses the three dimensional structure. In this paper, some 6-round impossible differential distinguishers are created, and hence extended to breakable 11-round 3D cipher based on these distinguishers. As a result, the time complexity of 10-round impossible differential attack on 3D is reduced to 2318.8. The technique of precomputation is widely applied, which offers a meaningful reference both on the actual attack of block cipher and to enhancement of efficient computation process.