The importance of the cholinergic system in the central nervous system lies in its regulatory role in cognitive functions, particularly in higher cognitive processes such as attention, memory, and learning. Cholinergic projection neurons from the basal forebrain regulate the activity of brain regions such as the hippocampus and prefrontal cortex through the release of acetylcholine. Research has shown that dysfunction of the cholinergic system is closely associated with various neurodegenerative diseases. In these diseases, degeneration of basal forebrain cholinergic neurons and the dysregulation of acetylcholine synthesis and transport are considered key contributors to cognitive impairments. Recent therapeutic strategies based on the cholinergic system for neurodegenerative diseases have shown certain therapeutic effects. Therefore, this paper primarily explores the impact of cholinergic system dysfunction on the development and progression of neurodegenerative diseases, aiming to deepen the understanding of the mechanisms underlying cholinergic system function and to provide more precise therapeutic approaches for neurodegenerative disorders.