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A relatively high proportion of vegetable waste is ever increasing in China in recent years, with the rapid development of agriculture. A large amount of spoiled vegetable waste also continues to accumulate. There is a serious threat to environmental health, due to a huge waste of resources. It is a high demand to treat this vegetable waste. Fortunately, anaerobic fermentation has been an important technical way to treat agricultural waste for clean energy. Meanwhile, the biogas slurry and biogas residue produced by fermentation can also be used as organic fertilizer to improve soil fertility. This study aims to clarify the effect of the additives on the thermostatic anaerobic fermentation and aerobic treatment of the mixed raw materials. The process was realized for the rapid conversion of biomass to biogas and biogas fertilizer. Firstly, the ratio of Volatile Solid (VS) was selected as 1:1:1 for the cow dung, tomato stems, and leaves. Three devices were utilized in the 0.56 m3 constant-temperature fermentation, including the no-adding, adding mass concentrations of 1 g/L urea, and 1 g/L plant ash. Among them, the Total Solid (TS) was 8%. The constant temperature batch was set as a fermentation temperature of (26±2)℃ and a period of 54 days during anaerobic fermentation. Secondly, the remaining biogas slurry was treated with the (30±1)℃ and 12 L/min aerobic aeration treatment for 8h. Some parameters were measured in the biogas production, including methane production, pH, Electrical Conductivity (EC), Oxidation-reduction Potential (ORP), Total Dissolved Solid (TDS), volatile fatty acid contents (VFAs), NH+ 4 -N contents change, biogas fertilizer biotoxicity, and nutrient contents. A comparison was then made to explore the effects of the combination of anaerobic fermentation with different additives and aerobic treatment of biogas slurry on the biogas and fertilizer production performance of the device. The results show that each addition after 28d before the reaction presented a significant effect on the systematic biogas production and methane synthesis. Specifically, the best performance was achieved in the urea group during the anaerobic fermentation phase. The cumulative biogas and methane production were 4 917, and 1 746.4 L, respectively, which increased by 91% and 128.7%, compared with the blank group, whereas, 12.6% and 69.4%, compared with the plant ash group. Furthermore, the methane volume fraction of 50% in the urea group and the total system biogas yield of 80% (namely 5 346 L) were all 5d earlier than that of the blank group. However, the total biogas production and total methane production in the whole cycle blank group were higher than in the other two groups. The fastest time was 1, 4, and 1h during the aerobic treatment phase, respectively, particularly for the complete biogas slurry ripening in the blank groups, plant ash, and urea groups. In this case, the germination indexes (GI) were 98%, 124.5%, and 100.4%, respectively, and the Total Dissolved Solids (TDS) were 5 670, 5 350, and 7 010 mg/L, respectively, while the volumes of NH+ 4 -N were 734.4, 538.1 and 862.1 mg/L, respectively. In summary, the best biological effectiveness and production quality of the biogas slurry were achieved in the urea group system. The standard is still needed for the nutrient supplement, or concentrated treatment, compared with the mixed liquid fertilizer. This finding can provide a strong reference to improve the biogas and fertilizer production quality of anaerobic fermentation, in order to reduce the secondary environmental pollution caused by the biogas fertilizer. [ABSTRACT FROM AUTHOR]