The invention relates to a solid solution multiferroic thin film, a preparation method and an electronic device comprising the multiferroic thin film and applied to a 5G storage technology. The thin film is a complex oxide solid solution with a pseudo perovskite structure, and the chemical formula of the thin film is (1-x<1>-x<2>)LM<(1-y) / 2>Fe<y>N<(1-y) / 2>O<3>x<1>Rx<2>Q, wherein y is equal to 0-1, x<1> is equal to 0-1, x<2> is equal to 0-1, and the sum of x<1> and x<2> is less than or equal to 1; L is selected from one or more of Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or Y; M and N are respectively selected from Mg, Ti, Hf, Co, Mn, Ni or Zr, and can be the same or different; R is LFeO3; Q is an oxide of L, M and N; and the thin film is a rhombohedral phase and orthorhombic phase solid solution and is polycrystal. The thin film has higher room-temperature electric polarization intensity and lower room-temperature leakage current density.