A firearm sight adjustment and installation tool is described. The tool serves to facilitate and expedite the accurate adjustment and/or installation of sights on the slides of a firearm, whenever the sights allow this adjustment. The tool includes a plate, a plate with nuts, tightening screws, a spacer block, at least one adapter, a drift screw, an interchangeable pushing element and quick reference featured on one of the plates. With the tool and little expertise, an individual may manually adjust both the front and rear sights of a firearm to increase the accuracy of the firearm without additional tools.