A Ti-based in-situ beta (β) reinforced Ti61.75Zr33.25Cu5 bulk metallic glass composite (BMGC) with unique hybrid microstructure and enhanced mechanical properties were produced using laser Powder Bed Fusion (L-PBF) with elemental powder mixture. The Ti61.75Zr33.25Cu5 BMGC possessed high compressive strength of 1.9 GPa with total strain exceeding 13%, and its microstructure was composed of fine primary β dendrite and amorphous phase in the inter-dendrite. The undissolved Zr particle induced stress accumulation near the particle interface that affected the local shear behavior in the β dendrite and promoted slip bands multiplication. The inhomogeneous distribution of amorphous phase divided the BMGC into strong and weak domains and caused strain partition, leading to back stress strain hardening of the BMGC. It is also found that there exist dispersed ω particles and ω laths in the primary β dendrites during the L-PBF and the deformation process, respectively, leading to high strength but limited plasticity of the BMGC. Further improving the mechanical properties of the BMGC can be achieved by hindering the ω formation through alloying method. This work provides a guidance on the design of novel additively manufactured BMGCs with outstanding mechanical properties using low cost elemental powder mixture.