Department of Physics, Fudan University, Shanghai 200433, China Topological quantum phase transition in the extended Kitaev spin model Shi Xiao-feng Department of Physics, Fudan University, Shanghai 200433, China Conclusion (1), From the ground-state energy, we show that this model displays a continuous quantum phase transition on the critical lines separating the Abelian and non-Abelian phases, where the third derivative of the ground-state energy is discontinuous. (2), we show that the discontinuity of the second derivative of the bipartite entanglement is related to the discontinuity of the third derivative of the ground-state energy. [1] A. Kitaev, Ann. Phys. (N. Y.) 321, 2 (2006). [2] C. W. Zhang, et.al., Proc. Natl. Acad. Sci. U. S. A. 104, 18415 (2007). [3] L. A. Wu, M. S. Sarandy, and D. A. Lidar, Phys. Rev. Lett. 93, 250404 (2004). [4] D. H. Lee, G. M. Zhang, and T. Xiang, Phys. Rev. Lett. 99, 196805 (2007); X. Y. Feng, G. M. Zhang, ang T. Xiang, Phys. Rev. Lett. 99, 196805 (2007). [5] X. F. Shi, Y. Yu, J. Q. You, and F. Nori, Phys. Rev. B 79, 134431 (2009).