In order to solve such problems as low yield,poor strength and high solid fuel consumption in the sintering process for a high proportion of limonite,a research on the collaborative optimization of thermal system and fuel structure is carried out,the effects of ignition time,holding time,fuel dosage and particle size composition on the sintering indexes are systematically investigated, XRD, optical microscopy and other detection methods are used to analyze the mineral composition and microstructure of the sinter. The results show that the yield of sinter,drum strength,utilization coefficient of sintering machine and solid fuel consumption are 73. 44%,68. 85%,1. 477 t/ (m²·h) and 67. 01 kg/ t,respectively, under the conditions of moisture content of the mixture of 7. 3%,anthracite ratio of 5. 42%,ignition time of 90 s and holding time of 90 s. On this basis,the fuel particle size composition is adjusted,and the proportion of ≤0. 5 mm and >5 mm particle size is appropriately reduced,and the proportion of 3 ~5,1 ~3 mm and 0. 5 ~1 mm particle size is set to 47. 86%,43. 13% and 9. 01%,respectively,so that the solid fuel consumption is further reduced to 66. 09 kg/ t,which is 3. 09 kg/ t lower than before optimization. The iron grade of the sinter reaches 57. 2%,and the main mineral facies are