We present a study of the growth and magnetic properties of Fe83Ga17 thin films prepared by the dc magnetron sputtering method, sputter deposited on Si(100) substrates for sputtering powers in the range 40W≤P≤80W. The structure and magnetic properties? of Fe83Ga17 thin films have been investigated by using X-ray diffraction analysis (XRD), scanning electron microscope (SEM)，physical property measurement system (PPMS) and magnetic force microscope (MFM). The results show that all samples exhibited a (110) disordered bcc structure, additional, the grain size of Fe83Ga17 thin films is about 40~70nm and the grain size slowly increases with increase in the sputtering power. The remanent magnetization Mr and the remanence ratio Mr/Ms tend to decrease slowly with increase in the sputtering power while the coercivity Hc and saturated magnetic field strength Hs go the opposite way. However, the changes in the saturation magnetization Ms are not so clear. The magnetic domain (MD) patterns showed the labyrinth structure and the domain size was increased with increase in the sputtering power.