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Purpose: To investigate the potential predictive factors of the visual change achieved with accelerated epi-on and epi-off corneal collagen crosslinking (CXL) in keratoconus., Methods: This retrospective comparative study analyzed 67 eyes treated with an accelerated epithelium-on (epi-on group) and epithelium-off (epi-off group) CXL. The clinical outcomes were evaluated and compared during a 1-year follow-up. Likewise, the relationship of the change achieved with both CXL techniques in the corrected distance visual acuity (CDVA) with different preoperative data was investigated., Results: The mean CDVA change at 3 months postoperatively was -0.04 ± 0.19 and -0.07 ± 0.25 in the epi-on and epi-off groups, respectively ( p  = 0.809). In the epi-on group, this change was significantly correlated with the preoperative apical ( r  = -0.375, p  = 0.045) and central corneal thickness ( r  = -0.402, p  = 0.031). In the epi-off group, the CDVA change was significantly correlated with not only the preoperative apical ( r  = 0.402, p  = 0.028) and central corneal thickness ( r  = 0.367, p  = 0.046) but also with some topometric and aberrometric indices ( r  ≤ -0.374, p  ≤ 0.042). Furthermore, the change in CDVA in the epi-on group could be predicted from age, preoperative refractive astigmatism J 45 component, anterior corneal asphericity, and posterior corneal high order aberration root mean square ( p  = 0.002, R 2  = 0.503). In the epi-off group, the CDVA change could be predicted from the preoperative minimum corneal thickness and magnitude of the vertical anterior corneal primary coma component ( p  = 0.001, R 2  = 0.446)., Conclusions: Clearly, different predictive factors of the visual change induced with the accelerated epi-on and epi-off CXL techniques are present, suggesting a different mechanism of action for stiffening the cornea and inducing changes in this structure., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Sidi Mohamed Hamida Abdelkader et al.)