There is a high risk of rejection of a corneal transplant known as a “rejection episode” in our Hospital conditioned by multiple variables. The aim of this article is to analyze the different risk factors of “corneal rejection episode” in post-transplant patients at one year of follow-up and in particular to consider the presence of donor blood incompatibility during the first year of post-surgical follow-up.A nested case-control study was designed in a cohort: observational, longitudinal, analytical and retrospective from year 2012 to 2013. We performed OR and logistic regression of the variables that influenced rejection.We included 101 consecutive transplants from multiorgan donation. The variables that influenced the rejection episode were: preoperative high risk group, graft size, blood incompatibility, female gender and age over 60 years old. Other variables such as the presence of comorbidities, combined surgery, surgical time greater than one hour and postoperative complications did not show significant differences.It is advisable to perform routine blood compatibility to reduce the risk of rejection.