Defects such as burrs and tear, often occur in the drilling of CFRP. Drilling characteristics of double cone drill was studied through analyzing the influence of chisel edge and primary drilling edge and secondary drilling edge on defects of hole’s entrance and exit and the influence regularity of processing parameters on tear factor. The results were compared with those of twist drill. Results show that, compared with twist drill, double cone drill is more suitable for drilling CFRP. The characteristics of double main cutting edge reduced the drilling axial force at hole’s entrance and exit, inhibited burrs and tear damages at hole’s entrance and exit. High speed drilling is favorable for minimizing the tear factor, the tear factor increases with the feed rate increasing. Through multi-linear regression analysis method, the prediction model between tear factor which is used to test hole’s entrance and exit of the two drill and process parameters were established.