to evaluate risk factorsof graft failure and allograft rejection after Penetrating keratoPlasty (PK). ·METHODS: Clinical dataof PKson 224 eyes (212 Patients) from 1996to 2006 were studied retrosPectively.the graft survival rate and rejection-free survival rateover 10 years were estimated with KaPlan-Meir's lifetable, and differences between levelsof each factor were comPared with log-ranktest. Cox regression was also Performedto further assessthe imPactof related clinical factorsonthe Prognosisofthe corneal graft. ·RESULTS:theoverall ratesof graft survival and rejection-free graft survival at 10 years after PK were 81.4% and 78.2% resPectively. Relatively higher riskof graft failure was associated with corneal vascularization, regraft, aPhakiaor PseudoPhakia, Presenceof anterioror Posterior synechia, long (≥90 minutes )oPerationtime andolder (≥60 years) ageof reciPient. Relatively higher riskof rejection was associated with corneal vascularization and longoPerationtime. Cox regression analysis showed corneal vascularization（RR = 2.46, P =0.04）, regraft (RR =5.67,P <0.01), aPhakia (RR = 3.64,P <0.05),or PseudoPhakia (RR =6.83,P <0.01), Presenceof anterior (RR =2.76,P = 0.05)or Posterior synechia (RR =3.12, P =0.05) were indePendent risk factors for corneal graft failure. ·CONCLUSION:the risk factors for graft failure after PK were corneal vascularization, regraft, aPhakiaor PseudoPhakia, Presenceof anterioror Posterior synechia.the risk factors after PK for allograft rejection were corneal vascularization and longoPerationtime.