The invention discloses a bio-organic fertilizer prepared from household waste through micro-biological degradation. The bio-organic fertilizer is prepared from the following raw materials: householdwaste, pond mud, pig manure, human and animal manure, bacteria sticks, slaughter house waste, Chinese medicine factory waste, waste green syrup, vinasse, dry branches, fallen leaves, a fermenting agent, an adsorbent and microorganism strains. The invention further discloses a preparation method of the bio-organic fertilizer. According to the preparation method, heat is generated during the metabolism of microorganisms, so that pathogenic bacteria, parasitic ova and weed seeds can be adequately killed; the bio-organic fertilizer contains a large quantity of beneficial microorganisms and is capable of fixing nitrogen, dissolving potassium and phosphorus and preserving moisture and fertilizers, and the living and breeding of harmful microorganisms can be inhibited during the rapid breeding ofthe beneficial microorganisms, so that the soil-borne diseases are reduced, the fertilizer preserving and supplying capacities of the soil are enhanced, a good soil condition is created for the growth of crops, and the disease resistance of the crops is improved; and by virtue of the beneficial microorganisms, the soil can be loosened, the gas permeability of the soil can be enhanced, the granular structure of the soil can be improved, the moisture and fertilizer preserving capacities of the soil can be improved, and the soil fertility can be increased, so that the quality of agricultural products is improved.