Abstract: In the view of investigating the sensitive degree of filling time and resin flow front shape to the material and processing parameters during liquid composite molding (LCM) processes, the sensitivity analysis method was introduced to study the resin infiltration process, in which both edge effect and curing reaction were considered. The mathematical relationships of the key physical parameters such as fluid pressure sensitivity and flow rate sensitivity were deduced, and then the filling time sensitivity equation and resin flow front shape sensitivity equation that represents the probability of defects formation were also established. Finally, the coupling method for calculating various parameters and the technical route of sensitivity analysis were designed. On these bases, a simulation program was self-developed to analyze the influencing degree of the key material and processing parameters on the development of resin flow patterns. The simulation results show that under constant injection pressure conditions, elevating the resin injection temperature is the most effective method to raise the production efficiency, and the decrease of edge permeability is the best way to improve the resin flow front shape and the resin infiltration result.