Introduction: Cytomegalovirus (CMV) infections remain amajor cause of morbidityafter solid organ transplantation (SOT) and allogeneic stemcell transplantation (SCT). The emergence of CMV resistanceto antivirals causes an increasing problem in transplantrecipients, complicating therapeutic and clinical management. We are reporting the first three transplant recipients who have CMV ganciclovir (GCV) resistance assessed by UL97viral gene sequencing in Turkey. Materials and Methods: Cytomegalovirus infection was monitored by quantitative viral DNA real-time PCR (Abbott Molecular) in plasmain transplant recipients, and CMV DNA positiveswas assessed by UL97 viral gene sequencing (ABI 3130) for GCV resistance. Results: After starting to look for UL97 GCV resistance in our center (since April 2012) we detected first renal transplantation and heart transplantation recipients who had CMV mutations in Turkey. Again the stemcell transplant recipient is the first case for pediatric stemcell transplantation having UL97 GCV resistant strain in our country. Conclusion: The start of VGCV maintenance treatmentafter an intravenous curative treatment while CMV DNA is still detectable in peripheral blood mightrepresent a risk factor for the emergence of CMV resistance. Our findings indicate that resistance to widely used ganciclovir as therapy, preemptive and prophylaxis should be monitored carefully in transplant recipients.