The invention discloses an organic compound fertilizer and a preparation method thereof. The organic compound fertilizer is composed of the following components in parts by weight: 15-20 parts of human manure, 4-6 parts of stable manure and 12-18 parts of industrial vinasse material. The preparation method comprises the following steps: proportionally and thoroughly mixing the human manure, stable manure and industrial vinasse, and stirring into a sludgy fertilizer. The human manure is processed by the following steps: fermenting the human manure in a methane tank for 10 days, laying a layer of corn or haulm straws according to the volume ratio of 1:2 or 1:3, layering a layer of human manure, spreading lime water which accounts for 30 vol% of the straws and human manure, covering a 5cm-thick soil layer, and composting at high temperature. The organic compound fertilizer can enhance the activity of various saccharides and enzymes in the soil, enable the plough layer of the soil to be loose and porous, and promote the formation of the crumb structure, so that the soil has high water retaining capacity; and the organic compound fertilizer solves the problem of low contents of water fertilizers and organic matters in the soil due to abundant use of chemical fertilizers by human.