The invention relates to high-
magnesium composite sinter and a production method thereof. A high-
magnesium fluxing agent and other raw materials are prepared, optimized and then sintered in a sinter
bed, so that the problems that in terms of existing high-
magnesium sinter production,
resource utilization and mineral generation are unreasonable, the yield is low, the strength is low, the return mine rate is high, and the
solid fuel consumption is high are solved. The high-magnesium composite sinter is formed by crushing and mixing sinter of upper and lower layer structures. With composite
calcium ferrite as the main binder phase, the upper layer of sinter is formed by
sintering a material A, wherein MgO accounts for not greater than 1.8%, and Al2O3 accounts for not greater than 2.0%; and the lower layer of sinter is formed by
sintering a material B, and the content of MgO of the lower layer of sinter is greater than that of the MgO of the upper layer of sinter. The material A comprises72-90% of iron-containing mineral
powder raw materials, 7-20% of a low-magnesium fluxing agent and 3-8% of a
solid fuel; and the material B comprises 0-90% of sinter, 0-70% of
sintering return mine and 10-100% of a high-magnesium fluxing agent. The high-magnesium composite sinter is good in comprehensive metallurgical performance, the
blast furnace burden structure can be optimized easily, and theslag mobility and desulfuration and
dealkalization effects can be improved.