Abstract: Cupola has many advantages, such as high efficiency, energy saving, continuous melting, good quality of liquid iron and large supply. We have improved the 35t/h cupola, and increased the depth of the furnace cylinder reduces the coke consumption by 14kg/t, the liquid iron temperature by about 30℃, and the erosion rate of the lining is reduced. The method of building slag-separator in layers is adopted to prolong the life of lining and reduce the material consumption. Design and use small slag separator to adjust the composition of liquid iron; Monitor the lining temperature and maintain the lining accordingly. It can meet the requirements of high quality and low cost of current products, and has achieved remarkable results.