Abstract: ObjectiveThe present study investigated characteristics and regulation of bio-organic fertilizer made by fermentation of filter mud from sugar refinery, in order to provide technical support for sustainable development of sugar-cane industry in Guangxi sugarcane planting area and offer reference for government to formulate agricultural planting and environmental protection policies. MethodField trial was conducted in important sugarcane planting area in Guangxi (Xingbin district in Laibin city, Daxin county in Chongzuo city) . Filter mud from sugar refinery was taken as raw materials and fermented into bio-organic fertilizer. Characteristics and fertilizer efficiency of the bio-organic fertilizer were studied.ResultBio-organic fertilizer fermented via functional bacteria rotted rapidly, hardly affected by environmental factors. Fermentation effects were stable, fermentation temperature could reach 77.2 ℃, and the temperature maintaining at 70.0-77.2 ℃ for 12 days. Organic matter content and organic acid conversion rate after fermented were 30.2% and 12.3%(abso-lute value) higher than those in traditional(natural) mode. Bio-organic fertilizer fermented via functional bacteria could im-prove yield of rice, cucumber and sugarcane greatly. Average yield of rice was 5971.5 kg/ha, an increase of 7.83% com-pared with the rice applied with bio-organic fertilizer fermented in traditional(natural) mode; average yield of cucumber was 76705.5 kg/ha, an increase of 41.18%, average yield of sugarcane was 118780.5 kg/ha, an increase of 6.91%.After application of bio-organic fertilizer fermented via functional bacteria, physical and chemical properties of soil were superior than those applied with bio-organic fertilizer fermented in traditional(natural) mode. In the soil, organic matter content was 15.75 g/kg, available nitrogen content 67 mg/kg, available phosphorus content 14 mg/kg, available potassium content 69 mg/kg. Utilization efficiency of nitrogen, phosphorus and potassium were 39.3% , 12.8% and 52.8% , respectively.ConclusionBio-organic fertilizer fermented via functional bacteria using filter mud from sugar refinery is better than fer-mentation in traditional(natural) mode. The advantages include rapid rotting speed, high fermentation temperature and long duration, superior organic matter content and organic acid conversion rate after fermentation. Meanwhile, it can increase the yield, soil fertility and fertilizer utilization efficiency. Therefore, it can be promoted for large scale application.