The invention discloses a flower soil formula and a preparation method thereof, and belongs to the field of plant planting soil. The flower soil formula and the preparation method thereof have the advantages that the formula is configured by honeycomb briquette residues, nutrients are sufficient, the breathability is good, the cost is low, low-carbon and environmental protection are achieved, andthe preparation time is short. The flower soil formula is prepared from, by weight, 40-45% of orchard soil, 8-15% of coal residues, 7-12% of leaf mold, 6-18% of river sand, 5-15% of plant ash, 5-15% of sawdust and 3-5% of field snail shells. The flower soil formula is particularly suitable for family potting planting.