The invention discloses a polyester fiber reinforced anti-cracking diatom ooze material, and a preparation method thereof. The polyester fiber reinforced anti-cracking diatom ooze material comprises, by mass, 15 to 35 parts of diatomite, 20 to 40 parts of heavy calcium carbonate, 8 to 20 parts of ash calcium powder, 8 to 20 parts of quartz sand, 2 to 5 parts of nanometer titanium dioxide, 1 to 4 parts of tourmaline, 0.5 to 2.5 parts of cellulose ether, 0.1 to 0.5 part of pregelatinized starch, and 0.1 to 2 parts of polyester fiber. According to the preparation method, diatomite, heavy calcium carbonate, ash calcium powder, quartz sand, nanometer titanium dioxide, tourmaline, and polyester fiber are taken as the raw materials, nontoxic and renewable adhesives cellulose ether and pregelatinized starch are also added, so that the obtained polyester fiber reinforced anti-cracking diatom ooze material possesses excellent cracking resistance and anti-pulverization ability; the preparation method is safe, and is friendly to the environment; production cost is low; and large-scale production can be realized easily.