Abstract: Aims to provide for optimal irrigation scheduling of tomato and to guide field management practices in areas under non-pressure subirrigation (NPSI). Characteristics of tomato (Lycopersicon esculentum L.)root distribution and regulating effects of biomass of aerial part were studied with two years investigating in greenhouse experiments. The experiment comprised of twelve non-pressure subirrigation treatments and one furrow irrigation (FI) as the control. Root samplings for root length and biomass at different growth periods and at harvest were determined using ascanner and Delta-T software. The results showed that root dense layer, root volume and primary root at different growth periods were influenced significantly by the water supply pressure and buried depth of emitter. The primary root length, root-shoot ratio and seedling index decreased significantly with water supply pressure increased at different growth periods, but total biomass showed the opposite trend. The root-shoot ratio, biomass and proportion of fruit dry weight to biomass were significantly higher with non-pressure subirrigation than that with furrow irrigation. However, the distribution proportion of dry matter of fruits increased with increasing of buried depth of emitter at maturation period, and the distribution proportion of dry matter of leaves and stems showed the opposite trend.