The Fe50Co50 magnetic films were prepared by magnetron sputtering onto glass substrates. The structural and magnetic properties of the films were investigated as a function of annealing temperature and annealing time. It is found that the films have the better crystallization orientation after annealing. The in-plane coercivity Hc reduces with increasing annealing temperature and annealing time. Coercivity reaches the minimum in the sample annealed at 600°C for 2h. Meanwhile, the saturation magnetization Ms increases with increasing annealing temperature as a whole. A scanning probe microscope was used to scan surface morphology and magnetic domain structures. After annealing, the domain size becomes larger and the contrast of domains increases.