Abstract:The anterior chamber(AC), a space bounded anteriorly by the cornea and posteriorly by the iris and the lens in the pupillary zone, is one of the most significant parameters in the anterior segment of the eye clinically. It is closely associated with the pathogenesis, progression, and treatment of various ocular diseases. Accurate preoperative assessment and utilization of anterior chamber depth(ACD)before surgery are crucial for achieving optimal postoperative visual outcomes. The term, effective lens position(ELP), has been introduced in recent years to better describe the postoperative position of the intraocular lens(IOL). To enhance the comprehension of ACD and ELP, this review elaborates on their definitions and interrelationship. It enumerates preoperative ACD measurement methodologies and compares the applicability of different devices. Furthermore, the review synthesizes its application on IOL power calculation and ELP prediction, recommending optimized formulas such as the Kane formula for scenarios with atypical ACD. The discussion extends to the impact of abnormal ACD on postoperative visual quality and relevant intraoperative interventions, aiming to provide evidence-based references for clinical practice.