To provide a telescopic shaft capable of being expanded or contracted with small frictional resistance and capable of transmitting large rotating torque even when the large rotating torque is applied, and a steering device equipped with the telescopic shaft.

When the rotating torque between a male intermediate shaft 16B and a female intermediate shaft 16A is equal to or lower than the predetermined torque, an upper surface 561 of a plate spring 56 and a side surface 411 of an axial groove 41 are rolling surfaces of a columnar pin 53, and the columnar pin 53 is rolled, and expansion and contraction action can be performed with the small frictional resistance. When the rotating torque between the male intermediate shaft 16B and the female intermediate shaft 16A is the predetermined torque, an elastic deformation amount of the plate spring 56 is equal to a space δ between the columnar pin 53 and a bottom surface 541 of a pin guide groove 54. As a result, the bottom surface 541 of the pin guide groove 54 and the side surface 411 of the axial groove 41 are rolling surfaces of the columnar pin 53, and the columnar pin 53 is rolled.

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