Abstract: An in-ground anchor structure for supporting posts for signs and the like includes a ground anchor assembly with an elongate ground penetrating spike and a mounting plate connected to the upper end of the spike in perpendicular relation thereto, and a post mounting assembly with a base plate to be received on and removably connected to the mounting plate of the ground anchor assembly and a post receiver formed as a hollow sleeve with an open upper end connected to the base plate and extending upwardly therefrom. The ground anchor assembly is driven into the ground until the mounting plate is flush with or slightly below the surface, the post mounting assembly is connected to the ground anchor assembly, and a post is secured to the sleeve. In an alternative embodiment the ground anchor assembly includes a screw shaft and screw plate in place of the spike.