Abstract: This work proposes a novel horizontal high-shear granulator for iron ore granulation before sintering process. The granulation behavior such as growth process and structure of granules were firstly analyzed, followed by the effects of operation conditions such as water content, initial particle size distribution, and the concentrate ratio. The results show that the granule size increased significantly with increasing the granulation time, and the structure of granule can be divided into three types: non-nuclei, single-nuclei, and multi-nuclei. Water promotes the coalescence and growth of particles, and a better granulation performance was obtained at the water content of 8.8wt% under the current raw material conditions. Increasing the nuclei particle ratio led to an increase in average size of granules and permeability of the granules bed, but a decrease in growth index. Besides, with increasing of concentrate ratio, granulation performance such as granule size, bed permeability, and uniformity became worse.