Abstract: The paper proposes a method to capture micron-sized particles in a three-dimensional fluid space by using bulk acoustic wave microstreaming traps.Two types of bulk acoustic wave microstreaming trap arrays were prepared,and the finite element method was used for simulation calculations.The first-order and second-order acoustic fields are obtained by solving the equations.The movement of polystyrene particles in the flow field was simulated and analyzed.The experimental results show that the bulk acoustic wave microstreaming traps can quickly and efficiently capture micron-sized particles in the three-dimensional fluid space.The experimental results are in good agreement with simulation results.Both cylindrical and circular hole bulk acoustic wave microstreaming traps can capture particles in three-dimensional space in tens of seconds.Moreover,the capturing efficiency of the cylindrical bulk acoustic wave microstreaming traps is higher than that of circular hole bulk acoustic wave microstreaming traps.This method breaks the limitation that the surface acoustic wave microstreaming traps cannot manipulation the particles in the threedimensional space,and improves the efficiency of capturing the particles.