This study reports the high impact toughness of polyamide 6 (PA6)/poly (vinylidene fluoride) (PVDF) blends achieved via adding an ionic liquid. The presence of the ionic liquid in the blends promotes the transformation of sea-island structure into co-continuous morphology, which to a large extent accounts for the improvement in toughness. In addition, it is believed that the enhanced mobility of the PA6 matrix by the ionic liquid also contributes to the high impact toughness.