The variation of mesophase textures of ethyl-acetyl celluose/ dichloroacetic acid solution with temperature was studied by polarizing microscopy and small-angle light scattering. It was found that the degree of order of polymer chains was different in different mesophase zones. When the solution was heated at a speed larger than 5 K/min, the mesophase with a relatively low degree of order could first transform into the isotropic phase. If the solution was heated slowly enough, however, the mesophase aggregates could become smaller, but the degree of order of polymer chains in the mesophase did not decrease with increasing temperature. When the solution transformed from the isotropic state to the anisotropic one, ordered domains were first formed, and then the disk-like texture appeared.