Abstract: The effects of the co-addition of B and Y on the microstructure and mechanical properties of a novel near α high temperature titanium alloy were studied. The solidification paths and the refinement mechanism of the titanium alloys with different B and Y additions were analyzed and studied. The results show that the addition of B and Y has a significant effect on the refinement of grain size of the Titanium alloys. The ultimate compressive strength and yield strength increase with the addition of B and Y, mainly due to the grain refinement caused by the addition of B and Y. The compressive plasticity and fracture toughness of the alloys decrease gradually with the addition of B and Y, which is attributed to the fractured TiB together with Y2O3 pulled out the matrix, accelerating the expansion of the crack.