A sewing machine includes a thread transferring mechanism automatically hooking onto thread hooking sections a needle thread which extends from a thread supply and which is retained in a predetermined thread preparatory path while retaining the needle thread so that the needle thread can be turned over to a needle threading mechanism, and a control unit which controls a thread tension adjusting unit so that tension applied to the needle thread becomes a predetermined tension that correlates with a transfer position of the needle thread transferred by the thread transferring mechanism.