The　design　of　a　new　tri-axial　accelerometer　to　measure　low　level　acceleration　for　low　frequency　vibration　is　described　in　this　paper.　The　accelerometer　is　mainly　composed　of　MEMS　(Micro　Electro-Mechanical　System)　acceleration　sensor　SCA610　and　ultra-low　power　microcontroller　MSP430　platform.　According　to　the　characteristics　of　the　acceleration　sensor　SCA610,　a　method　to　accomplish　the　differential　output　of　the　SCA610　is　proposed.　Meanwhile,　other　methods　based　on　hardware　and　software　were　used　to　realize　the　noise　reduction.　The　experimental　results　show　that　the　accuracy　of　the　accelerometer　is　effective　to　meet　the　demands　of　low　level　acceleration　measurement.