A method for cyclically preparing titanium sponge and coproducing sodium cryolite using sodium fluotitanate as an intermediate material, which includes the following steps: A) adding hydrofluoric acid to titaniferous iron concentrate to enable a reaction to form fluotitanic acid; B) adding sodium carbonate and sodium hydroxide to the fluotitanic acid to enable a reaction to form the sodium fluotitanate; C) putting the sodium fluotitanate into a reactor, adding aluminum to react with the sodium fluotitanate to form the titanium sponge and sodium cryolite; D) extracting the sodium cryolite and sending it to a rotary reaction kettle together with concentrated sulphuric acid to enable a reaction to form hydrogen fluoride gas and sodium sulphate, aluminum sodium sulphate; collecting the hydrogen fluoride gas and dissolving it into water to obtain a hydrofluoric acid solution; E) recycling the obtained hydrofluoric acid to Step A to leach the titaniferous iron concentrate.