Recent clinical studies and multimodal neuroimaging evidence have revealed that patients with obsessive-compulsive disorder（ OCD） primarily exhibit impairments in inhibitory control， cognitive flexibility， and working memory updating within executive functions. Attention deficits primarily manifest as difficulty disengaging from threat-related information， and memory impairments are characterized by impaired episodic memory retrieval and insufficient metamemory confidence. In terms of neural mechanisms， the aforementioned deficits are closely associated with dysfunction in the prefrontal-striatal circuit and impaired coordination between large-scale brain networks such as the executive control network and the default mode network. This paper reviews behavioral manifestations and neural mechanisms of OCD patients across three major cognitive dimensions of execution， attention， and memory， so as to elucidate the role of cognitive deficits in symptom occurrence and maintenance. The paper further emphasizes that multidimensional cognitive impairments， coupled with network dysregulation， collectively form the foundation for persistent OCD symptoms， aiming to provide a systematic reference for understanding pathological mechanisms and developing targeted intervention strategies.