Abstract: The transformation of force and the force ratio were investigated in the Ta12W scratching with brazed single crystal diamond grit, and the wear morphology of diamond during scratching process was observed as well. Through the acoustic emission (AE) experiment of brazed single diamond grit scratching on Ta12W, the AE signals of wear characteristics of diamond grit were captured to spectral analysis and power spectrum analysis. Experimental results show that the abrasive wear of diamond scratching on Ta12W can be divided into three stages, i.e. initial wear stage, steady wear stage and acute wear stage. Meanwhile, the scratching force and force ratio were distinctly different from each wear stages. The frequency band of the single diamond abrasive wear of AE signals ranged in 0~170 kHz, and the main peak frequency of power spectrum ranged in 7.8~27.3 kHz. The main peak frequency transformed from high frequency to low frequency with the increase of grit wear, and the peak frequency of power spectrum also increased.