Abstract: PVDF/PP/PETG/basalt fiber composites were prepared by a melting blending method. The rheological behavior, morphology, mechanical properties, and heat resistance of the blends were investigated using rotary rheometer，scanning electron microscopy, material testing machine, and Vicat softening point machine in detail. It was found that PP, PVDF and PETG were pairwise immiscible, in which PP and PVDF formed a bicontinuoud phase and PETG presented in the system as spherulite particles. The poor mechanical properties of PVDF/PP/PETG blends were improved after basalt fiber was introduced. The tensile strength and flexural strength of PVDF/PP/PETG composite increased to 21.9 MPa and 44 MPa when the content of basalt fiber was 30 wt%. Vicat softening point of PVDF/PP/PETG composite was increased from 126.7 ℃ to 141.7 ℃.