A thread holding mechanism of a sewing machine which holds a thread supplied from a thread supply source includes a thread gripper unit that grips one end of a supplied thread, and a thread presser unit structured in a unified manner with the thread gripper unit and provided between the thread gripper unit and the thread supply source. Provided at the thread-supply-source side is a thread guide that guides another end of the thread, and when the thread gripper unit descends below the thread guide, the thread presser unit abuts the thread.