Copper chalcogenide nanoparticles, particularly Cu_2–xE (E = S, Se, Te; 0 ≤ x ≤ 1), have gained significant interest in recent years due to their distinct physical and chemical properties, making them highly versatile for a wide range of applications. Among these, copper selenide nanoparticles (CS NPs) have attracted special attention due to their remarkable characteristics, which can be tailored through various modification strategies, providing significant potential for the diagnosis and treatment of neurological diseases. This review summarizes emerging trends and explores future perspectives on the use of CS NPs for diagnosing and treating central nervous system diseases, including glioblastoma and neurodegenerative disorders.