To provide a cold-formed steel pipe having a tensile strength of ≥490 MPa and a low yield ratio without performing SR (stress relieving) treatment, and to provide a method useful for producing the cold-formed steel pipe.

The cold-formed steel pipe has a prescribed chemical componential composition, and the microstructure of the steel sheet is composed of a polygonal ferrite phase of 4 to 70 area%, a pseudo-polygonal ferrite phase of 0 to 20 area%, a martensite phase of 0 to 5 area% with an aspect ratio (major axis/minor axis) of ≤4.0, and the balance bainite phase, and, the steep pipe has a cold-formed part in which, provided that the sheet thickness is defined as t(mm) and the outside cold bending diameter is defined as d(mm), t/d is ≤10%.