Background; In-stent restenosis after implantation of sirolimus-eluting stents (Cypher짰) still occur in some cases and delayed stent strut fracture was recently suggested as a new potential mechanism. Bx Velocity stent (Cordis), the platform of Cypher stent was one of the popular stents in the past bare-metal stent era, but there was no reported case of stent fracture so far. We experienced 7 delayed strut fracture cases of Cypher stent at routine follow up coronary angiography. Method & Results; Mean age of the patients was 64.7짹8.4 year and 4/7 cases were male patients. 4 cases showed complete strut disruption and the remaining 3 cases showed partial strut fracture. The mean length of the stent was 28.3짹4.3mm and the mean diameter was 3.3짹0.3mm. The fractured sites were at the mid portion of the stents in all cases. The initial average inflation pressure was 15.0짹3.0 atm and no adjuvant ballooning was performed in all cases. 4 cases (57%) revealed focal angiographic restenosis just at the stent fracture site and TLR was performed.in 2 cases. Conclusions; Although, the data regarding Cypher stent fracture is very limited so far and its exact mechanisms are unknown, physicians should raise their consideration and further investigation should be performed in the future. The tendency to perform long stenting in DES era and structural stent characteristics alteration by drug carrier vehicle can be the possible mechanisms of Cypher stent fracture.