The invention relates to organic carbon suspension liquid compound fertilizer and a preparation method of the organic carbon suspension liquid compound fertilizer. The organic carbon suspension liquid compound fertilizer comprises, by weight, 18.1-26.5 parts of organic carbon, 0.4-7.2 parts of nutrient substances, 10-12.5 parts of suspending agents and 25.0-33.0 parts of water. The organic carbon suspension liquid compound fertilizer can resolve the unbalanced fertilizer application state of carbon hunger of crops, is complete in nutrient, promotes better growth of the root systems of crops, improves the yield and quality of crops, effectively prevents the carbon hunger symptom of crops, and improves the adverse resistance of crops such as cold resistance, drought resistance and disease resistance.