Abstract: An adjustable wrench includes a head formed on one end of a tube and having an opening for slidably receiving an engaging member. The tube has a bore communicating with the opening for rotatably and slidably receiving a rod. The rod is threadedly engaged with the head for moving the engaging member toward and away from the tube for allowing the engaging member to engage with fasteners of different sizes. A handle is secured to the rod for rotating the rod and for moving the engaging member toward and away from the fastener.