Abstract: One of the important ways to improve the mechanical properties of continuous glass fiber reinforced nylon 6 composites (cGF/PA6) is to improve the interface interactions between glass fiber and nylon 6. In this study, star-branched polyamide 6 (SPA6) was applied to cGF/PA6 composite system, and continuous glass fiber reinforced nylon composites with different contents of SPA6 (cGF/PA6-SPA6) were prepared by melt extrusion combined with hot pressing. The characterization of contact angle indicates that the polarity between SPA6 and cGF is more similar. DSC results show that there is not much difference in the melting temperature among PA6, SPA6 and PA6-SPA6 composite matrix, and both the crystallization temperature and crystallinity of PA6-SPA6 are increased. The flexural strength of PA6-SPA6 matrix is lower than that of PA6 and SPA6 measured by three-point flexural tests. However, compared with cGF/PA6, the flexural strength of cGF/5wt%SPA6 and cGF/10wt%SPA6 composites increased by 4.9% and 6.4%, respectively, and the shearing strength of cGF/5wt%SPA6 and cGF/10wt%SPA6 composites increased by 16.7% and 15.6%, respectively. The impact strength of cGF/PA6 and cGF/SPA6 composites is 12 times and 26.3 times that of PA6 and SPA6, respectively. Combined with the observation of impact fracture morphology, it can be inferred that adding 5wt% or 10wt% SPA6 to cGF/PA6 composites can improve the flexural and shearing strength of the composites, while having little influence on the impact strength, and considering its cost-effectiveness, it proves to be of practical value for applications.