Objective  Evaluate the safety and effectiveness of transepithelial， very high fluence accelerated corneal collagen cross-linking （A-CXL） in primary keratoconus. Methods  Self-control study. Thirteen primary keratoconus eyes of 13 patients were treated with transepthelial， very high fluence A-CXL with a UVA intensity of 45 mW/cm2， an irradiation time of 2 min 40 s， and a total energy of 7.2 J/cm2. Routine ophthalmologic examination， UCVA， BCVA， refractive error， corneal keratometry， anterior and posterior elevation （AE and PE）， index of vertical asymmetry （IVA）， minimum corneal thickness （CT）， compensated intraocular pressure （IOPcc）， endothelial cell density （ECD） were evaluated pre-operatively and 7-day， 1-month， 3-month， 6-month， 12-month post-operatively. Results  The UCVA （F=6.111， P＜0.01） and BCVA （F=9.734， P＜0.01） showed a statistically significant improvement by 12-month post-operatively. The decrease in spherical lens （F=5.871， P＜0.05）， steeper K-value （F=19.651， P＜0.05）， Kmax （F=3.253， P＜0.05）， AE （F=23.958， P＜0.01）， PE （F=20.832， P＜0.01） and IVA （F=4.068， P＜0.05） were statistically significant. CT （F=4.180， P＞0.05）， ECD （F=1.812， P＞0.05） and IOPcc （F=0.332， P＞0.05） were without significant change. Conclusion  Transepithelial， very high fluence A-CXL is safe and effective in treating primary keratoconus.