The Lens Dysfunction Syndrome includes two widespread ocular disorders: presbyopia and cataract. Understanding its etiology, onset, progression, impact, prevention, and treatment remains a significant scientific challenge. The lens is a fundamental structure of the ocular dioptric system that allows for focus adjustment or accommodation to view objects at different distances. Its opacification, primarily related to aging, leads to the development of cataracts. Traditionally, lens alterations have been diagnosed using a slit lamp and later with devices based on the Scheimpflug camera. However, both methods have significant limitations. In recent years, optical coherence tomography (OCT) has become a valuable tool for assessing the lens and pseudophakic intraocular lenses (IOLs) in clinical practice, providing a highly detailed non-invasive evaluation of these structures. Its clinical utility has been described in assessing the shape, location or position, and size of the lens, as well as in determining the degree and type of cataract and its various components. Regarding pseudophakic IOLs, OCT allows for the accurate assessment of their position and centering, as well as for detecting possible complications, including the presence of glistening or IOL opacification. Furthermore, OCT enables the evaluation of the posterior capsule and its associated pathologies, including late capsular distension syndrome. This review highlights the key applications of OCT in the assessment of the lens and pseudophakic IOLs.