The Gamma-ray Large Area Space Telescope (GLAST) is an international and multi-agency space mission that will study the cosmos in the energy range 20 MeV - 1 TeV. GLAST is an imaging gamma-ray telescope more much capable than instruments flown previously. The main instrument on board of the spacecraft is the Large Area Telescope (LAT), a high energy pair conversion telescope consisting of three major subsystems: a precision silicon tracker/converter, a CsI electromagnetic calorimeter and a segmented anti-coincidence system. In this article, we present the status of the construction and tests of the silicon tracker.