In order to achieve high performance BMI matrix composite manufactured by vacuum bag cure only technique, a novel additive WD-01 was selected to modify BMI-B resin based on modified polyetherketone (PEK-C) toughened 4,4′-bismaleimidodiphenyl methane (MBMI)/O,O′-diallybisphenol A (DABPA) system, and the properties of WD-01 modified BMI resin (BMI-WD) and resin matrix composite were investigated here. Results indicated that the cure shrinkage rate of BMI-B resin was reduced from original 4.0% to 1.8% and the surface morphology of neat resin casting were changed significantly by incorporating 1 wt.% WD-01, no change of chemical cure behavior of BMI resin was observed. Vacuum consolidated BMI-WD/T700 laminates had autoclave cure quality with excellent mechanical properties. A high performance of vacuum-bag curable prepreg with promising characteristics is being developed and expected to find use in advanced composite structures.