An adjustable wrench with strength enhancing structural design includes a body including a grip end and a driving head. The driving head includes a fixed jaw and a movable jaw. The movable jaw engages and is operably movable in a groove. The groove includes two lateral walls facing oppositely and spacing from each other. Each of the two lateral walls includes a first surface and a second surface. The first surfaces of the two lateral walls face oppositely and are separated by a space. The first and second surfaces of each of the two lateral walls have a common edge and an included angle less than 90 degrees. The movable jaw includes two slopped surfaces corresponding to and abutting against the second surfaces of the two lateral walls.

A wrench includes a body having two openings. The body has a chamber in which two operation members are movably located. Each operation member has a first jaw and a second jaw respectively formed on two ends thereof. The first jaws each have a first face protruding out from the first opening. The second jaws each have a second face protruding out from the second opening. Two resilient members are located in the chamber and bias the two operation members to let the two first jaws and the two second jaws are opened wide. The first and second jaws each have slots which are engaged with the lips on each of the openings. The first jaws protruding from the opening form an open wrench, and the second jaws protruding from the other opening form another open wrench.