The invention provides a preparation method for flake zinc powder containing indium, bismuth, aluminum and calcium. The preparation method includes the following steps: step A, 100-300ppm of the bismuth, 100-300ppm of the indium, 0-150ppm of the aluminum and 0-200ppm of the calcium are added into pure zinc ingots when an intermediate frequency furnace is used for melting the pure zinc ingots at a temperature of 500 DEG C to 600 DEG C; and step B, after a mixture of the indium, the bismuth, the aluminum, the calcium and the pure zinc ingots is alloyed, compressed air is jetted for blowing the mixture to form zinc powder, and then the zinc powder after alloying is ground in a dry mode under certain conditions to form the flake zinc powder. The zinc powder obtained through the preparation method contains the trace amount of indium, the trace amount of bismuth, the trace amount of aluminum and the trace amount of calcium and then is ground into the flake zinc powder, and therefore the effect that the anti-corrosion time of a Dacromet coating containing the flake zinc powder and the anti-corrosion time of a Cr-free Dacromet coating containing the flake zinc powder are prolonged can be achieved.