The effect of boron oxide (B2O3) on the microstructure and strength of 20% (by volume) silicon carbide (SiC) reinforced molybdenum disilicide (MoSi2) composites was examined. Microstructural analysis using optical and electron microscopes was performed. A standard four-point bending test and Weibull statistics were applied to evaluate the flexural strength of the composites. The addition of boron oxide to composite was found to reduce the processing temperature and the grain sizes, result in formation of glassy boundary phase, and to increase the flexural strength of the composite.