Abstract: To improve the processing flowability and mechanical property of carbon fiber reinforced polyamide (CFRPA) composites, polyamide amine (PAMAM) dendrimer was used as flow modifier when the CFRPA was prepared from melt compounding. DSC, electromechanical universal testing machine and SEM were employed to characterize the crystallization behavior of the modified polyamide 66 (PA66) and the mechanical properties, microstructure morphology of CFRPA, respectively. Results indicate that by the addition of PAMAM, the fluidity of PA66 can be significantly improved and the viscosity of CFRPA melt blends can be effectively reduced. When the addition of PAMAM is 1wt% of PA66 matrix, a maximum crystallinity of 12.75% of PA66 is achieved. The melt flow rate (MFR) is increased to 112 g/10 min, which is 814.47% higher than that of the unmodified PA66. Correspondingly, the equilibrium torques of the CFRPA with different CF contents during melt blending are reduced, and CF can be uniformly dispersed in the PA66 matrix. CFRPA has a maximum tensile strength as high as 118 MPa with CF content of 40wt%.