Using a fiber laser to explore the key parameters of laser radial sharpening the resin-bonded cubic boron nitride (CBN) grinding wheels, a systematic research is carried out, which consists of the test of pulse overlap rate of optical fiber laser ablating resin-bonded wheels, optical fiber laser ablating resin-bonded wheels and optical fiber laser ablating resin- bonded CBN grinding wheels. The results, which have been testified by grinding experiments, show that the best pulse overlap rate is 30% ~50% , the best single pulse laser power density is distributed in the range of 5×107~7.5×107 W/cm2, the sharpening depth with a good performance is 39 μm , surface roughness of workpiece is 0.789 μm . The narrow and shallow traces of grinding are obtained.