This study introduces Hystrix aegeanensis n. sp., a new late Miocene (MN 12) porcupine species from Samos, Greece, and Karaağaç, Türkiye. This represents the fifth record of late Miocene Hystrix from Europe and Asia Minor. H. aegeanensis n. sp. exhibits a unique occlusal outline and pattern compared to those of all other late Miocene Hystrix species. This study further clarifies the systematic divergence among late Miocene Hystrix species based on occlusal outlines and patterns. The first group, including H. parvae, H. primigenia, H. gansuensis, H. brevirostra, and H. lufengensis, exhibits a simple occlusal pattern and an oval/square occlusal outline. In contrast, the second group, comprising H. aegeanensis n. sp., H. kayae, and H. aryanensis, displays a more complex occlusal pattern and a rectangular occlusal outline on their upper cheek teeth.