A sewing machine includes a sewing portion, a detector, a processor, and a memory. The sewing portion includes a needle bar and a transport portion. The needle bar is configured to have a sewing needle on a lower end. The transport portion is configured to move a work cloth. The detector is configured to detect ultrasonic waves. The memory stores computer-readable instructions that instruct the processor to perform specifying a position of a transmission source of the ultrasonic waves based on the ultrasonic waves that are detected by the detector, specifying sewing information based on the specified position of the transmission source, the sewing information being information that pertains to sewing, and controlling the sewing portion based on the specified sewing information.