A novel hybrid composite with low-melting-point alloy fillers was fabricated and characterized through differential scanning calorimeter analysis and viscosity test. Based on the chemo-rheological properties of the hybrid composite, the hybrid interconnection process was determined. The effect of the reduction capability of hybrid composite on the rheology-coalescence-wetting phenomenon of low-melting-point alloy fillers into the hybrid composite was investigated. The hybrid composite has a low viscosity and did not show excessive curing around the melting point of the used low-melting-point alloy material. The low-viscosity characteristic of hybrid composite and the loading of reductant accelerated rheology-coalescence-wetting phenomenon of low-melting-point alloy fillers in hybrid composite significantly. X-ray image and cross-section view revealed a stable metallurgical interconnection between upper and corresponding lower electrode in hybrid composite with reduction capability. This stable metallurgical interconnection was reflected in much improved mechanical and electrical properties of the hybrid interconnection.