To provide a grease composition free from ignition even in the case of coming into contact with a high temperature material and excellent in combustion resistance, and thereby usable on the surroundings of a blast furnace or the like.

The grease composition comprises a base oil and a thickening agent as the main materials, and it contains further a water absorbing polymer and water. The grease composition can prevent ignition even in the case of coming into contact with a high temperature material (for example, 500-600°C). In the case of water only, it is hardly becoming homogeneous with the base oil and the thickening agent, but the using of the water absorbing polymer together with water can improve homogeneity. In this case, the preferable amount of the water absorbing polymer is 0.02-15%, especially 0.1-3% based on the whole amount of the grease composition. Further, water is compounded preferably in an amount of 5-80%, especially 5-60% based on the whole amount of the grease composition.