In order to pursue energy-saving, economic, lightweight as the goal, the so called transformation-induced plasticity (TRIP) effect was utilized to solve the contradiction for improving strength and plasticity simultaneously for steel products. Hence, following the above mentioned technology, a series of 1 GPa grade TRIP-assisted bainitic ferrite (BF) steel products were produced, while the microstructure, strength and ductility were investigated for steels subjected to various type of microstructural controlling. The results show that the steel with the microstructure composed of c.a. (75~85)% of bainitic ferrite and ≥15% of retained austenite may be acquired advantageously. For that purpose the reasonable chemical composition design and the initial hot-rolled steel was controlled to be with the microstructure composed of (20~30)% of ferrite and (70~80)% of needle-like bainite as the prerequisite, thereby, the comprehensive mechanical properties could be ensured for 1 GPa grade TRIP-assisted BF steel. The reasonable proportion of a dual phase structure and the morphology features have great influence on the strength and ductility of the TRIP-assisted BF steel. While the lamellar retained austenite with the width within the range of 80~130 nm were distributed uniformly in the matrix structure of 82% bainitic ferrite, through the compatible deformation between dual phases the excellent comprehensive mechanical properties were achieved, namely the elongation rate was 20.3%, and the product of tensile strength and ductility reached to 22.0 GPa· %. The strength reached to 1099 MPa when the lath width of bainitic ferrite was within the range of 0.15~0.45 μm and the width of lamellar-like retained austenites was within the range of 50~90nm. When the steel was subjected to a sudden collision the residual austenites(about 6%)may be induced to response a secondary TRIP effect so that to increase its energy absorption ability, hence improving the anti-collision ability of the relevant automobile parts.