In view of the cow dung in the process of aerobic fermentation production of biological organic fertilizer, due to improper parameters of the fermentation cycle is long, the poor quality of fertilizer, and fruit branch waste recycling use difficult problems. Cow dung and walnut twigs were used as raw materials, carbon-nitrogen ratio, fungicide and the number of days between turns were taken as the experimental factors, germination index, organic matter content and total nutrient content were used as test indexes. On the basis of a large number of single factor tests, selecting the optimal level of multi-factor orthogonal test, the optimal combination process was determined. Test results showed that when the carbon nitrogen ratio was 25, inoculants bacteria agent B, the number of days between turns were 4 days, aerobic fermentation of cow manure heated up quickly, high temperature maintenance time was long, fermentation cycle was short, the organic fertilizer produced by fermentation had a high degree of maturity fermentation biological. The effective viable count (cfu) was 2×108 per gram, the total nutrient content was 14.86%, and the germination index was 96.6%. The results can provide the necessary theoretical basis for the large-scale treatment of cow dung and the resource utilization of walnut twigs.