The changes in gel characteristics of soy protein as a result of various reagents that alter specific interactions which affect the formation and textural properties of gels, were studied. The reagents were added to 15% soy protein solutions prior to heat treatment. The gels were not formed with urea, indicating that hydrogen bonds significantly contributed to the formation and hardness of soy protein gel. Hydrophobic interactions and disulfide bonds compensated for hydrogen bonds and the contributions of electrostatic interactions to gel hardness are relatively insignificant. The farce primarily responsible for gel cohesiveness appeared to be disulfide bonds, because a significant decrease in cohesiveness was found only with the presence of N-ethylmaleimide. Adhesiveness decreased only with the addition of urea, and thus the contribution of hydrogen bonding to adhesiveness of gel could be concluded to be resent. However, adhesiveness was suggested to be interpreted not only wile molecular forces involved in gel formation but also with hydration properties of protein.