The single Bi 4-x Eu x Ti 3 O 12 and Ni 1-x Cu x Fe 2 O 4 films were prepared via spin-coating method. The composite films of the Bi 3.4 Eu 0.6 Ti 3 O 12 /Ni 0.7 Cu 0.3 Fe 2 O 4 , annealed under N 2 , air and O 2 , were also prepared via the same method. Compared with the films of Bi 4 Ti 3 O 12 , the films of the Eu-doped Bi 4 Ti 3 O 12 (Bi 4-x Eu x Ti 3 O 12 ) exhibit enhanced ferroelectricity. And when x is equal to 0.6, the films of Bi 4-x Eu x Ti 3 O 12 show optimal ferroelectricity. Compared with the undoped NiFe 2 O 4 film, in the films of Ni 1-x Cu x Fe 2 O 4 , the doping of Cu 2+ enhances ferromagnetism. And when x is equal to 0.3, the Ni 1-x Cu x Fe 2 O 4 films exhibit optimal ferromagnetism. For the composite films of Bi 3.4 Eu 0.6 Ti 3 O 12 /Ni 0.7 Cu 0.3 Fe 2 O 4 , annealing atmosphere has a significant impact on the magnetoelectric properties. In comparison with the composite films annealed under N 2 and air, the composite films annealed under O 2 exhibit optimum ferroelectricity (saturation polarization being 26.3 μC·cm −2 ), ferromagnetism (saturation magnetization being 385.6 emu·cm −3 ) and enhanced magnetoelectric coupling effect (magnetoelectric voltage coefficient being 86.4 mV·(cm·Oe) −1 ). This is beneficial for the applications in magnetoelectric functional devices.