One new high performance modified BMI resin matrix with enhanced processing characteristics, made from 4,4-bismaleimidodiphenyl methane (BDM) and allyl phenyl compounds, allyl epoxy resins and epoxy acrylate resins, were developed. Solubility, differential scanning calorimetry (DSC), gel time, and Fourier transform infrared (FTIR) spectroscopy were used to detect the structure and processing characteristics of the modified BMI resin and neat BDM. Results show that the new modified BMI resin systems have enhanced processability compared with neat BDM, especially improved solubility and faster thermal polymerization rate. In addition, the new cured systems have more than two times improved impact strength without a great decrease in excellent dielectric properties or thermal and hot-wet resistance of neat BDM resin.