The present invention relates to a two-stage roasting mineral smelting integrated technique of laterite, and especially to the extracting and recovering of nickel, cobalt and iron in the low-grade nickel oxide ore. The laterite, additive and reducing agent are crushed into a granularity smaller than 5mm and are delivered into a rotary kiln for reduction roasting for a time period. The roasting temperature is controlled so that the material does not loop and is controlled lower than a softening temperature. After taking out from the kiln, the material is delivered into an intermediate-frequency heater for executing a two-stage roasting. The temperature is controlled so that the material flows out with a half-smelted state and enters into a water quenching pool for water quenching. After taking out and grinding, magnetic separation is executed for eliminating the non-magnetic impurity. Then the magnetic concentrate, namely the coarse ferronickel is obtained. The coarse ferronickel is refined with a conventional electric furnace for obtaining the ferronickel product. The aim of the invention is to process the laterite. The nickel, the cobalt and the iron are reduced to simple substances through reduction roasting. Then the nickel and the cobalt are separated along with the iron through the magnetic separation. The coarse ferronickel is generated and the ferronickel product is obtained after refining. The two-stage roasting mineral smelting integrated technique of laterite according to the invention has the advantages of simple technique, low cost, high recovery rate and easy generalization.