Purpose <p>To explore the positional relationship between intraocular lens (IOL) and crystalline lens (CLL) by anterior segment optical coherence tomography (AS-OCT) in high myopia complicated with cataract eyes.</p> Study design <p>Retrospective and consecutive study.</p> Methods <p>Patients who had undergone phacoemulsification with IOL implantation were reviewed. Exclusion criteria were any ocular history that could have affected the zonules, poor pupil dilation and intra- or post- operative complications. The magnitude and direction of tilt and decentration of CLL and IOL, CLL thickness (LT), anterior chamber depth (ACD) and axial length (AL) were measured.</p> Results <p>Fifty eyes without high myopia (EM group) and 73 high myopia eyes (HM group) were recruited. The magnitude of tilt and decentration of CLL was significantly different between the HM and EM group (p_{tilt HM vs. EM} &lt;0.01, p_{decentration HM vs. EM} &lt;0.01). In terms of the decentration, the magnitude of IOL was significantly higher than of CLL in both the HM and EM groups (p _HM &lt; 0.01; p _EM=0.043). Multivariate analysis showed that only the alignment of CLL was related with the position of IOL in both group (R² _{tilt EM}=0.237, p _{tilt EM} &lt; 0.01, R² _{decentration EM}=0.097, p _{tilt EM}=0.042; R² _{tilt HM}=0.476, p _{tilt HM} &lt; 0.01, R² _{decentration HM}=0.359, p _{tilt HM} &lt; 0.01).</p> Conclusions <p>Alignment of CLL in high myopia eyes determines the position of the IOL. Moreover, the IOL in high myopia was more decentrated, while this discrepancy did not reach a level that would compromise visual quality, it needs to be taken into consideration.</p>