Individuals with borderline personality disorder (BPD) frequently display impairments in the identification of emotional facial expressions paralleled by a negativity bias. However, it remains unclear whether misperception of facial expressions is a key psychopathological marker of BPD. To address this question, the authors examined 43 women diagnosed with BPD and 56 healthy female controls using an emotion face identification task and a face dot-probe task together with measures on psychopathology. Compared to controls, women with BPD showed impaired identification of disgusted and angry faces concurrent with a bias to misclassify faces as angry, and a faster preconscious vigilance for fearful relative to happy facial expressions. Increased severity of borderline symptoms and global psychopathology in BPD patients were associated with reduced ability to identify angry facial expressions and a stronger negativity bias to anger. The findings indicate that BPD patients who misperceive face emotions have the greatest mental health issues.