To report a unique case of a 31-year-old woman developing corneal ectasia after an abandoned laser-assisted in situ keratomileusis (LASIK) procedure with incomplete flap creation without laser ablation. A 31-year-old Taiwanese woman presented with corneal ectasia after a failed LASIK with an incomplete flap creation without laser procedure in her right eye 4 years ago. A visible scar was observed in the flap margin from the 7 to 10 o'clock position. The auto refractometer revealed myopia with high astigmatism, -1.25/-7.25 × 30. Keratometry was 47.00/40.75 D. In contrast, no sign of keratoconus was found in the fellow eye, which did not experience any surgery. Corneal tomography indicated that the incomplete flap scar was compatible with the main area of corneal ectasia. Furthermore, anterior segment optical coherence tomography showed a deep cutting plane and a relatively thin corneal bed. Both findings explained the cause for corneal ectasia. Corneal ectasia can occur whenever corneal structure or integrity is compromised.