NOVELTY - Iron(II) disulfide semiconductor thin film is prepared by ultrasonically oscillating and cleaning surface of a deposition substrate; adding iron powder into ferrous sulfate or ferrous chloride solution to obtain cationic precursor solution, and reacting sodium hydroxide solution with sulfur to generate sodium polysulfide solution as anionic precursor solution; depositing surface of deposition substrate with iron(II) disulfide thin-film layer by soaking substrate into cationic precursor solution and into anionic precursor solution; and performing vulcanizing heat treatment.    USE - Method of preparing iron(II) disulfide semiconductor film (claimed) used for thin film solar battery.    ADVANTAGE - The method has short process, low cost and good production quality, and is suitable for large-scale continuous production. The prepared film is controllable in thickness and composition, and compact and uniform in appearance, has good crystallinity and photoelectric property.    DETAILED DESCRIPTION - Preparation of iron(II) disulfide semiconductor film comprises:    (A) treating surface of a deposition substrate by ultrasonically oscillating and cleaning the surface of the deposition substrate;    (B) preparing 0.01-10 M ferrous sulfate or ferrous chloride aqueous solution and then adding 1-20% iron powder to obtain cationic precursor solution, and preparing anionic precursor solution by putting 0.1-10 M sodium hydroxide solution under water bath heating condition, adding 1-40 mass% of sulfur and reacting to generate sodium polysulfide solution;    (C) depositing surface of deposition substrate with iron(II) disulfide thin-film layer by soaking substrate into cationic precursor solution for 2-60 seconds and washing with deionized water for 10-60 seconds, then soaking into anionic precursor solution for 2-60 seconds and washing with deionized water for 10-120 seconds, and repeating the soaking steps to obtain thin-film layers of different thickness on the deposition substrate; and    (D) performing vulcanizing heat treatment on the thin-film layer deposited substrate under protective atmosphere at 200-800 degrees C for 10-300 minutes using carrier gas to feed sulfur source.