Background: The quality of the donor cornea, which basically depends on the condition of the endothelial sheet, is an important factor for the successful outcome of penetrating keratoplasty. Patients and Methods: In this retrospective study, we present our experience in using trypan blue staining for the examination and evaluation of 498 consecutive corneal grafts from 251 donors, concerning their suitability for penetrating keratoplasty, during the decade 1986–1995. Results: Forty-two grafts out of 498 (8.5%) were considered not suitable for surgery because of the great number of destroyed cells (cell density less than 1,500 cells/mm<sup>2</sup>) and the abnormal cell size and cell shape. Nine out of the 456 (1.97%) operated eyes exhibited primary donor failure and needed re-operation, probably because of boundary cell density of the graft (ranged in those cases from 1,600 to 1,800 cells/mm<sup>2</sup>). No infections of grafts were observed. Conclusion: Tissue evaluation of corneal grafts by the use of trypan blue staining is a simple, cost-effective, safe and accurate method that does not influence the vitality of the endothelial layer of the grafts.