Brachial artery pseudoaneurysms (PSA) are considered uncommon, but they can be limb and life threatening. Most etiologies are related to iatrogenic injury or following a fracture. Here we present a 37-year-old male complaining of a large swelling in his right upper arm that was gradually increasing in size for the last 7 months. It started with a sudden onset of pain while lifting heavy boxes at his daily job. Ultrasound and MRA showed a pseudoaneurysm of the right brachial artery. Resection of the PSA was performed with a vein interposition graft. This case illustrates the significance of considering PSA as a differential diagnosis in patients presenting with upper arm swelling without history of obvious trauma.