The invention discloses an organic fertilizer and a preparation technology thereof. The organic fertilizer is prepared from the following raw materials in parts by weight: 15 to 20 parts of paddy rice straw, 10 to 15 parts of corn straw, 10 to 15 parts of soybean straw, 5 to 15 parts of rapeseed cake meal, 6 to 9 parts of urea, 15 to 20 parts of diammonium phosphate, 10 to 20 parts of potassium dihydrogen phosphate, 5 to 10 parts of ferrous sulfate, 5 to 10 parts of manganese sulfate, 15 to 25 parts of cow dung, 20 to 40 parts of duck manure, 15 to 20 parts of chicken manure, and 12 to 20 parts of pea powder. The organic fertilizer contains elements such as nitrogen, phosphor, potassium, and the like, and a large amount of organic substances, is capable of promoting the fruiting and maturing of crops, and at the same time can enhance the performance of crops on preventing lodging, hot wind, and drought. Furthermore, the fertilizer can loosen soil, relieves the phenomenon of soil hardening, improves the fertilizing performance of soil to achieve the goal of increasing yield, reduces the damage of chemical fertilizer to soil, and provides balanced and enough nutrients for the growth of crops. The investment is low, and the yield is high. Moreover, the quality of crops is improved, and the economic benefit is increased therefore.