He Xiantu (Traditional Chinese: 賀賢土, Simplified Chinese: 贺贤土) (Sep. 28, 1937-) is a theoretical physicist in China. He is the chief scientist of many Chinese national nuclear research and development programs. He designed the first neutron bomb in China.
He served for a long time in the physical institutes of the Chinese Academy of Science, and he is the former deputy director of the Institute of Applied Physics and Computational Mathematics (IAPCM), Beijing. He currently is the chief scientist of National 863 Program Hi-Tech Inertial Confinement Fusion (ICF) Project and the chief scientist of IAPCM. He also holds the professorship and the dean position of the College of Science, Zhejiang University. He became an academician of the Chinese Academy of Sciences in 1995's election.
He is a member of the Expert Committee of Nonlinear Science, Major State Basic Research. He made great contributions to the development of nuclear weapons in China. He has been long working on inertial confinement fusion ICF model, nonequilibrium statistical physics, and nonlinear plasma physics.