Taking tomato cultivar‘ Dongnong 708’ as experimental material，and 3 layers soil from ground
surface（ 0-15 cm，15-30 cm，30-45 cm） as cultivation soil，applying N、K fertilizer as the contrast and N、
P、K fertilizer as treatment，this paper studied the effects of different soil depth and phosphorus level on tomato
biomass and root morphology．Results showed that the biomass of above ground tomato plant was affected by both
P application level and soil depth．In all 3 soil layers，every index at P application treatment was significantly
higher than that in the contrast，and at the same P level，all indexes at 0-15 cm layer were significantly higher
than the other layers．However，the underground biomass，total root length，root surface area，root volume and
root length between 0-1.5 mm diameter were greatly influenced by P application level and the effect by soil depth
was not obvious．In conclusion，soil depth and P level both can affect the biomass of aboveground tomato，and
P application at soil surface was more beneficial for accumulation of tomato biomass．The root morphology was
influenced greatly by P application level，but not by soil depth.