Abstract: Four beam lines are constructed for the 6MV Tandem Accelerator of Peking University.Various ions such as ~1H, ~(12)C, ~(16)O, ~(19)F, ~(35)Cl, ~(79)Br, etc. are accelerated. Some experiments are made, such as deuterium determination for the first time by the D(~(12)C, p)~(13)C nuclear reaction,hydrogen profiling using the resonance reaction ~1H(~(19)F, αγ)~(16)O, backscattering analysis for highT_c superconductor YBa_2Cu_3O_(7-x), ERDA induced by 35 MeV of ~(35)Cl and 45 MeV of ~(79)Br ions foranalyzing of light elements in various materials and stopping power measurements of low energyheavy ions and other experiments.