We have studied the morphology and distribution of atomic steps on Si(001) with scanning tunneling microscopy. We find that native oxide removal at temperatures up to 1350 K leads to step pinning and bunching. Cleaning at temperatures above 1450 K leads to regular step distributions which reflect the macroscopic misorientation of the sample. Steps running parallel to the 2×1 dimer rows on the upper terrace are straight, whereas steps perpendicular to these rows are ragged.