ABAQUS finite element software is used to simulate the cutter to cut the glass fiber bar. The influences of cutting speed, cutting depth, cutting angle and cutter arc on the cutting force of cutter are analyzed. The study shows that the cutting force and volatility of the cutter increase with the increase of cutting depth. It is recommended that the cutting depth of glass fiber bar should not exceed 4 mm with the cutting pick. The cutting force of cutter does not change significantly with the increase of cutting speed. The fluctuation degree (standard deviation) of the cutting force becomes significantly larger when the cutting angle is less than 70°. It is recommended that the cutting angle should not be less than 70°. Considering the service life of the cutter, the tip arc is recommended not to be less than 2 mm.