Abstract: An object of the present invention is to provide, for example, a polyethylene powder that can produce a shaped article excellent in balance between mechanical strength and a rate of thermal shrinkage even when shaped at a high speed. Provided is a polyethylene powder having intrinsic viscosity IV of 1.5 dL/g or more and 15.0 dL/g or less measured in accordance with ISO1628-3 (2010), an amorphous moiety thickness of 5.3 nm or larger and 12.0 nm or smaller, and a crystallite size of 13.9 nm or larger and 18.0 nm or smaller obtained by a reflection method of X-ray diffraction.