This study aims to design and fabricate a new kind of radiation shielding composite against both neutron and gamma rays. Based on Monte Carlo simulations, novel (W+B)/6061Al composite sheets with different W mass fractions (40-70%) were first fabricated by ball-milling and SPS followed by hot-rolling, then the microstructure and mechanical properties were investigated. Results show that after rolling process, W and B particles uniformly distributed in the matrix and the interface of W-Al exhibited good metallurgical bonding containing solid solution. The composites were mainly consisted of W and Al phases. EBSD results show that W particles had the effects of promoting dynamic recrystallization (DRX) nucleation, confining the grain growth and reducing the texture of 6061Al matrix. Through tensile tests, the composite with 50 wt.% W shows the highest strength and better plasticity. Together with the simulation results, composite of this composition is believed to meet the demand of practical applications. The strengthening mechanisms of (W+B)/6061Al composites include dislocation strengthening and load transfer effect.