Continuous cropping of tomato for processing in monoculture is commonly practiced, and there have been some problems with reduced germination and plant growth and declining production under continuous cropping sequences. Even soil microbial and physicochemical properties to be the main factor for the barrier, changes in its composition and community structure in a certain extent reflect the quality and integrity of the soil. A pot experiment was conducted to explore effects of continuous mono-cropping and addition activated charcoal into soil on the microflora and enzyme activities of the soil grown tomato for processing. The tested soil in the experiment had been planted with continuous mono-cropping tomato for processing for 3 seasonal crops, and had a severe continuous obstacle. The experiments had 5 treatments with 6 replicates for each treatment, including CK (cropping 1 season soil, 1a), 2a (continuous mono-cropping 2 season soil), 3a (continuous mono-cropping 3 season soil), 2a+C (continuous mono-cropping 2 season soil with the addition of activated charcoal), 3a+C (continuous mono-cropping 3 season soil with the addition of activated charcoal). There tomato seedlings were transplanted to clay pots (40 cm diameter and 50 cm depth, 20 kg soil) at Apr 25, 2008. The results were as follows. Continuous mono-cropping affected the microbial and enzyme activities for the tomato for processing to some extent. With increasing corroping years, Catalase activity increased, and Urase、Saccharase、Polyhenol oxidase and Phosphatase activities decreased respectively. Activated charcoal could improve growth of processed tomato plants to greater extent, and, for example, plant height, stem thick, fresh weight and biomass of processed tomato plants grown in mixed with activated charcoal soil were significantly higher than those in without activated charcoal addition soil. In addition, after adding activated charcoal to soil, activities of Urase, Invertase, Phosphatase and Polyhenol oxidase were higher than control (without activated charcoal addition), but Catalase activity decreased. The number of bacteria in rihzosphere decreased with increasing year of cropping, the number of bacteria decreased 12.1% and 16.8% respectively at 2-year and 3-year, while the numbers of fungi and actinomycete increased, the numbers of fungi and actinomycetes were higher 20% and 60% and 1.04 and 1.12 times than control (1-year), respectively.With adding activated charcoal to soil, the number of bacteria increased 5.8% and 1.6% respectively at 2-year and 3-year, while the numbers of actinomycetes and fungi decreased 13.0% and 23.1% and 8.3% and 50%, respectively. The number of antisulphate increased, but the numbers of nitrifier bacteria and aerobic azotobacter declind respectively. The results suggested that autotoxic effect of tomato for processing on the microbial and enzyme activities were declined after adding activated charcoal to soil, continuous cropping obstacle was also alleviated progressively.