In order to study the effects of moulding depth on root characters of maize,maize was moulding up with 0 cm,5 cm,10 cm,15 cm and 20 cm of soil in field experiment.Support root numbers,dry weight of support root,support root layer numbers and underground root dry weight were investigated.The result showed that support root numbers and support dry weight of per plant were the most in 10cm treatment.Moulding depth was negative related to support root numbers and support root dry weight,and significantly negative related to support root layer numbers,and significant positive related to underground root dry weight.Support root layer numbers was significantly negative related to underground root dry weight.