The invention relates to an organic compound fertilizer suitable for flower planting. The organic compound fertilizer comprises the following constituents in percentages by weight: 20-25% of plant straws, 10-15% of cow dungs, 20-30% of shell powder, 8-12% of powdered rock phosphate, 20-30% of plant shells, 3-6% of humic acid and 3-5% of biological bacteria, wherein the sum of the constituents is 100%. The organic compound fertilizer prepared according to the formula is prepared by the following specific steps: mixing the plant raw materials according to the corresponding proportion, adding humic acid and the biological bacterial strains into the mixed raw materials according to the corresponding proportion, uniformly stirring, retaining the moisture to be 50-55%, performing stacking fermentation for 10 days, then turning over the stacks, feeding the fermented materials into a flap type fermentation tower to be fermented for 12 days, fermenting by an aerobic fermentation method, keeping the water content of the mixed and fermented plant raw materials to be 20%, when the fermented materials are free of stink obviously, discharging the fermented materials from the fermenting tower, uniformly and fully mixing the fermented materials with the powdered rock phosphate, performing over crushing, screening and qualification inspecting, and at last pelletizing or grinding into powder, so as to obtain the finished product of the dedicated fertilizer for the flower.