Abstract: A Bragg detector was designed and built to be used in accelerator mass spectrometry measurements at China Institute of Atomic Energy.The detector has an(applied) electric field parallel to the incident direction and sufficient gas pressure to stop the particle.The initial experiments with α particles of ~(241)Am and ~(26)Mg particles were performed.The detector's total energy and Bragg peak resolutions are ΔE/E<1.4% and ΔZ/Z<4.1% for ~(26)Mg particles with 49.7 MeV kinetic energy,respectively.