Purpose: To examine the effect of immediate irrigation on ocular alkali burn. Methods: Information on the injury, immediate irrigation, and ocular findings was retrospectively obtained from each patient’s record. Results: 36 patients (49 eyes) irrigated their eyes with tap water (the irrigation group) and 17 patients (29 eyes) did not (no irrigation group). The mean age of patients in the irrigation and no irrigation groups was 30 and 53 years, respectively. According to Hugher’s classification, 76% of eyes in the irrigation group had grade 1 injury, while 86% of eyes in the no irrigation group had grade 2 injuries. Mean time from the injury until healing was 8 days in the irrigation group and 29 days in the no irrigation group, respectively. Conclusion: Immediate copious irrigation with tap water reduced the severity in alkali burns of the eye and shortened the healing time.