Abstract: Phosphorus (P) is one of the most important macronutrient elements for plant growth. High residual P in greenhouse soils was frequently found because P is relatively insoluble and has a long residence time in the soil. In order to find an optimal level of soil available phosphorus for tomato production, a pot experiment was conducted to investigate the effect of phosphorus (P2O5) on tomato yield, phosphorus partitioning in different organs of tomato, dry matter accumulation, soil available P and enzyme activities. The results showed that with the increase of P application rate, the content of available P in soil and P content in all organs of tomato significantly increased. The tomato yield, signal fruit weight and dry matter accumulation reached maximum when P2O5 were 0.53 g/kg. The optimal content of soil available P was 60-77 mg/kg for tomato production. Excessive P application (0.53 g/kg) caused a high accumulated P in soil and plant, resulting in the salt toxicity, low soil enzyme activities, declined dry matter and low tomato yield.