A quick-turning wrench includes a driving end with a first jaw and a second jaw. The first and the second jaws respectively have a first and a second side, which face one another. The driving end defines an engaging space between the first and the second jaws. The driving end has a first grip-surface section, a second grip-surface section, and a third grip-surface section. The engaging space is partially delimited by the first, the second, and the third grip-surface sections. The first grip-surface section is adjacent to the first side and extends along a flat first phantom surface. The second and the third grip-surface sections are adjacent to the second side and respectively extend on a flat second phantom surface and a flat third phantom surface.