Root morphological/exudation traits and growth of phosphorus-solubilizing bacterial in response to different levels of phosphorus fertilization are critical mechanisms for increasing phosphorus uptake efficiency of plants and saving fertilizer inintensive vegetable cropping system. Field experiment was conducted with Solanum lycopersicum(S. lycopersicum)with T0(no phosphorus fertilizer)，T0.5P(100 kg/hm²，reducing phosphorus fertilizer by 50% based on the conventional phosphorusapplication)，T0.8P(160 kg/hm²，reducing phosphorus fertilizer by 20% based on the conventional phosphorus application)and TP(200 kg/hm²，the conventional phosphorus application). To elucidate mechanisms of phosphorus uptake under condition with reducing phosphorus fertilization，shoot biomass and phosphorus uptake as well as root morphological (root length density and specific length)and exudation traits(rhizosphere carboxylate content)of S. lycopersicum were measured at 15，30 and 45 d after crops transplanting. The abundance of soil phosphorus-solubilizing bacterial functional genes(phoD，phoC and pqqC)were also quantified. Compared with conventional phosphorus application，reducing 50% phosphorus fertilization increased root specific length，rhizosphere exudation of carboxylates and the abundance of microbes encoding phoC and pqqC genes at 30 and 45 d after S. lycopersicum transplanting. There was a significant positive correlation between the abundance of phoC and pqqC genes in phosphorus solubilizing microorganisms and the specific root length and rhizosphere organic acid secretion of tomato roots. Reducing 20% phosphorus fertilization improved shoot phosphorus content of S. lycopersicum at maturity as compared with those with conventional phosphorus application. There was a high potential for reducing phosphorus fertilization in intensive vegetable cropping system. Maximizing the root morpho-physiological plasticity and stimulating growth of soil phosphate-solubilizing microbes are the most important processes for achieving high production and high phosphorus efficiency.