Abstract: A water meter wrench adapted to loosen or tighten the meter's box ring or its equivalent while the meter is in its installed location - usually below the ground in a meter box. The wrench comprises a tubular main stem having a torque stabilizing bar attached to its upper end and a pair of water meter engaging forks attached to a support at its lower end, the distance between the forks being selectively adjustable. Within the tubular main stem is carried a socket drive shaft having a head at its upper end and a box ring engager at its lower end. In use, the box ring is engaged by the engager, the separation between the water meter forks is adjusted for the size of the meter, and the forks are engaged with the inlet and outlet portions of the meter. Next, the socket drive shaft is torqued in the desired direction, as with a socket or torque wrench, the drive shaft in turn torquing the box ring engager and hence the box ring.