The uniaxial tensile behavior of ultra-high performance concrete containing coarse aggregate（UHPC-CA） was experimentally studied. The coarse aggregate content， steel fiber content and aspect ratio were selected as the main variables. The acting mechanisms of steel fiber and coarse aggregate were revealed. The results show that the uniaxial tensile strength and deformation performance of UHPC-CA decrease with the increase in coarse aggregate content， while the increase in steel fiber content and aspect ratio has a great enhancement effect on the tensile properties of UHPC-CA. There is a good interfacial bonding strength between the steel fiber and matrix. After cracks occur in the matrix， the tensile stress is mainly borne by the bonding force. The incorporation of coarse aggregate weakens the uniformity of the spatial distribution of steel fibers， and introduces the weak coarse aggregate-matrix interfacial transition zones， which adversely affect the tensile properties of UHPC-CA.