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The effects of Ti content to the microstructure of high-boron steel were studied by using SEM and XRD. The effects of Ti on impact properties at room temperature, high-temperature mechanical properties and oxidation resistance at 850 °C of the steel were researched by using impact tester, dynamic thermal-mechanical simulation testing machine and oxidation weight increase method. The experimental results showed that the boride granules which distributed in a discrete manner within the matrix exhibited a round and smooth morphology and the boride size decreased greatly after adding Ti. The optimization of boride morphology and distribution made the absorbed impact energy of the steels increased. TiC particles would precipitate and ferrite would form after adding Ti. At a low level of boron content, the high temperature mechanical properties increased with increasing of born content, while at a higher level of boron content, the high temperature mechanical properties had little change. Optimum high temperature mechanical properties were obtained when boron content was at 0.33wt.%. The 850 °C oxidation test results of the steels pro and after adding Ti were all in accordance with grade 2 oxidation resistance standard in GB/T 13303-1991. Ti was conducive to the improvement of the high temperature oxidation resistance properties.