Purpose: To report 2-year outcomes of trans-epithelial accelerated corneal collagen cross-linking (TE-ACXL) procedure in the treatment of progressive keratoconus patients. Patients and Methods: Twenty-four eyes from 24 patients who underwent TE-ACXL (6mW/cm.sup.2 for 15 minutes) were included in this retrospective interventional study. Best-corrected visual acuity (BCVA), keratometry values, thinnest corneal thickness (PachyMin) and topometric indexes were analysed preoperatively and at 6-month, 12-month, 18-month and 24-month postoperative. Progression was assessed by increase greater than or equal to1.00D in maximum keratometry (Kmax); increase greater than or equal to1.00D in corneal astigmatism; decrease greater than or equal to2% in PachyMin; increase greater than or equal to0.42 in D-index. Results: There were no complications during or after TE-ACXL. No significant differences (DELTA) were observed between baseline and 12-month or 24-month postoperative: DELTABCVA (-0.08 + or - 0.25, p=0.190; -0.04 + or - 0.17, p = 0.588), DELTAKmax (-0.08 + or - 1.32, p=0.792; -1.04 + or - 1.89, p=0.135), DELTAAstigmatism (-0.15 + or - 0.89, p=0.485; -0.24 + or - 1.38, p=0.609), DELTAPachyMin (-0.56 + or - 15.70, p=0.882; 0.56 + or - 18.74, p=0.931), DELTAIndex Surface Variation (DELTAISV) (-2.11 + or - 10.27, p=0.395; -4.67 + or - 17.32, DELTA=0.442), DELTAIndex Vertical Asymmetry (DELTAIVA) (-0.05 + or - 0.17, p=0.208; -0.08 + or - 0.26, p=0.397), DELTAIndex Height Decentration (DELTAIHD) (0.00 + or - 0.02, p=0.368; -0.01 + or - 0.04, p=0.484), DELTAKI (0.00 + or - 0.05, p=0.851; 0.01 + or - 0.06, p=0.877) and DELTAD-index (0.15 + or - 1.14, p=0.512; 0.06 + or - 1.36, p=0.892). Eleven to 33% of patients had disease progression at 24-month postoperative according to the parameters used to determine progression. Conclusion: Although some patients maintain disease progression, TE-ACXL seems to be a safe and effective treatment for keratoconus over the 2-year follow-up period. Studies with longer follow-up periods and larger patient cohorts are recommended. Keywords: cornea, keratoconus, disease progression, transepithelial, cross-linking