Zhongjiazao 17 and wufengyou T025 were used as experimental materials, three levels of steel slag power(0, 450, 750 kg/hm2) with equal application of nitrogen, phosphorus and potassium were designed to study the effects of steel slag powder on the growth，yield and heavy metals content of rice in the double cropping paddy field during 2014—2015. The results showed that, compared with the treatment with no steel slag，the treatments with steel slag increased by 10.1%–25.8%, 14.3%–29.4% and 4.6%–6.2% in root growth, root activity at the late growth stages and grain yield respectively. Meanwhile, they increased by 2.4% and 3.7%, 6.6%, 2.1%, 11.1%, 5.4% in the nitrogen, phosphorus, potassium, silicon and pH value of the soil，respectively. They had little influence on the contents of Hg, Cd, Pb, As, Cr and Mn in the soil.