A support assembly for mounting a solar panel unit, including: a base unit including a plurality of base tubes that are spaced apart from one another, and two connecting tubes that are respectively connected to opposite end portions of each of said base tubes, a supporting unit including a plurality of limiting components each permitting at least two of the base tubes to extend therethrough so as to position said at least two of the base tubes relative to each other, and a plurality of supporting rods each connected to and extending upwardly from a corresponding one of said limiting components and adapted for supporting the solar panel unit thereon; each of said limiting components has a main body portion that is formed with two through holes spaced apart from each other, and two extending portions that are spaced apart from each other and that extend upwardly from said main body portion, each of said through holes being disposed for permitting a respective one of said base tubes to extend therethrough, characterized in that the connecting tubes are detachably connected to the base tubes, the supporting rods are detachably connected to the limiting components, each of said extending portions being disposed for permitting a respective one of said supporting rods to be sleeved fixedly thereon, and the support assembly is adapted to be mounted on a ground, the main body portion of each of said limiting components being further formed with an aperture, the supporting unit further including a plurality of positioning components, each of said positioning components extending through said aperture of said main body portion of a respective one of said limiting components and adapted to extend into the ground for mounting fixedly a corresponding one of said limiting components on the ground. a base unit including a plurality of base tubes that are spaced apart from one another, and two connecting tubes that are respectively connected to opposite end portions of each of said base tubes, a supporting unit including a plurality of limiting components each permitting at least two of the base tubes to extend therethrough so as to position said at least two of the base tubes relative to each other, and a plurality of supporting rods each connected to and extending upwardly from a corresponding one of said limiting components and adapted for supporting the solar panel unit thereon; each of said limiting components has a main body portion that is formed with two through holes spaced apart from each other, and two extending portions that are spaced apart from each other and that extend upwardly from said main body portion, each of said through holes being disposed for permitting a respective one of said base tubes to extend therethrough, characterized in that the connecting tubes are detachably connected to the base tubes, the supporting rods are detachably connected to the limiting components, each of said extending portions being disposed for permitting a respective one of said supporting rods to be sleeved fixedly thereon, and the support assembly is adapted to be mounted on a ground, the main body portion of each of said limiting components being further formed with an aperture, the supporting unit further including a plurality of positioning components, each of said positioning components extending through said aperture of said main body portion of a respective one of said limiting components and adapted to extend into the ground for mounting fixedly a corresponding one of said limiting components on the ground.