Pseudoaneurysms (PAn) are uncommon in adults and even less common in children. They are most often encountered after iatrogenic arterial injury. Presentation may be substantially delayed after the iatrogenic event, and diagnosis can be difficult, especially when the PAn occurs in an unexpected location. Treatment of PAn has evolved during the last two decades from a reliance on surgical resection to US-guided compression, coil embolization, covered stents, and stent-graft exclusion. More recently, direct percutaneous US-guided thrombin injection has been used in the treatment of PAn. We present three cases of successful PAn thrombosis by US-guided percutaneous thrombin injection in children, one of the epigastric artery and two of the femoral artery.