A frame structure for solar cell module is disclosed, which has four sidebars and each sidebar is comprised of a bottom, a first vertical wall, a second vertical wall, a first horizontal wall and a second horizontal wall in a manner that the first vertical wall is formed with a width larger than the second vertical wall; the second vertical wall is connected to the bottom and spaced from the first vertical wall by a first distance; the second horizontal wall is connected to the first vertical wall by an end away from the bottom; the first horizontal wall is connected to the first vertical wall and is spaced from the second horizontal wall by a second distance; the second horizontal is formed with a thin panel at a side that is proximate to the first horizontal wall for blocking the overflow of a filling material in the frame structure.