Changing protein polymerization structure is an effective means to obtain different functional properties. The aggregation morphology of proteins is highly dependent on their composition and polymerization conditions. Thermal polymerization conditions with pH value below the isoelectric point will bring about great changes in polymerization structure of protein component. The research focused on the aggregate type of heatinduced gels from various components of soy proteins (soluble whole protein, 7S, 11S, acidic subunit, basic subunit) at low pH value（1.5~3.5）. The results of rheological properties, texture properties, polymer morphology and driving force for aggregation showed that most soy protein components formed finestranded gels at pH value of 20, and the aggregation of acidic subunit and 7S was more fibrillation. The particulate gel networks at pH value of 3.5 were composed of particles or clusters. Compared with particulate gels, the apparent viscosity of fine stranded gels was decreased significantly, with relatively low gel hardness and elasticity. The gelation property of 7S was the worst at the same pH value among different protein components. The main driving force of the fine stranded gels was hydrophobic interaction of noncovalent bond, and covalent disulfide bond for particulate gels. The relationship between the structure and functional properties of different soybean protein components at low pH value provided sound basis for different applications.