To provide a flexible shaft structure for securing an equal or the same transmission characteristic at normal rotation time and reverse rotation time by arranging a rightward rotating flexible shaft and a leftward rotating flexible shaft, and joining the respective flexible shafts in the middle or the center of the using length of both flexible shafts.

This flexible shaft structure has a plurality of winding layers by a stranded wire group by successively spirally winding the stranded wire group in the inverse direction on a conductor, and is provided with the rightward rotating flexible shaft 10 and the leftward rotating flexible shaft 16, and is characterized by joining both flexible shafts 10 and 10 in the middle or the center of the using length of both of these flexible shafts 10 and 16.