Oscillatory measurements were used to investigate the effect of temperature and concentration on the viscoelastic and gelling properties of basil seed gum (BSG). Linear viscoelastic region was determined by strain sweep and it was found in 0.5% strain. Storage modulus (G′) was greater than loss modulus (G″) in all concentrations and they increased by improving BSG concentration. Yield stress value was determined by stress sweep and it increased from 1.40 to 7.47 Pa when BSG concentration increased from 1% to 3%. Frequency sweep showed BSG solution was a typical weak gel, and complex viscosity (η*) had linear correlation with frequency. The effect of temperature on gel forming was investigated during heating (20–90 °C) and cooling (90–20 °C) phases. BSG was characterised as a thermo-reversible gel and did not have thermal hysteresis. Gelling temperature was raised as BSG concentration was increased. Exhibiting special rheological properties of BSG makes it as a proper synergistic gel, which can be applied in real food systems such as dairy desserts.