Abstract: TA15-based composites with Nano-TiB distributed in grains and N dissolved in the titanium matrix were prepared by low-temperature and high-pressure sintering and hot rolling using boron nitride nanosheets(BN) as reinforcement,and the effects of BN content on the microstructure and mechanical properties of the composites were investigated. The results show that the intragranular distribution of Nano-TiB and solid dissolution of N are mainly attributed to the diffusion of B and N elements into the titanium matrix during the holding process before rolling. The intragranular distribution of Nano-TiB has excellent load transfer, inhibition of fracture and promotion of dislocation accumulation. The mechanical properties of the composites are mainly determined by the content and distribution position of Nano-TiB and the solid solution of N together.When the BN addition is 0.025wt%, the strength and plasticity of the composites are simultaneously enhanced compared with those of the TA15 matrix, and the tensile strength reaches 1375.16 MPa and the elongation is 13.89%. When the BN content exceeds 0.025wt%, it is easy to form Nano-TiB agglomerated zone, which can lead to a significant decrease in the plasticity of the composites.