In this study, we extracted galactan from the seaweed Gracilaria verrucosa of Vietnam and investigated its structure and properties. The seaweed was immersed in water in the different temperatures to obtain the solution of galactan. Thereafter, the solution was coagulated and purified to obtain galactan as a powder. Kjeldahl method, infrared spectroscopy, viscosity determination and differential scanning calorimetry (DSC) were used to characterize structure and properties of the resulting material. It was found that the obtained galactan had agar structure without sulfate as substitute group. The proteins content, the intrinsic viscosity and the thermal resistance of the galactan extracted in water at 40 oC were higher than those of the galactan extracted in water at 100 oC.