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Rheological properties of two cellulose derivative solutions which exhibit liquid crystalline behavior under certain conditions were determined by using a capillary rheometer. Measurements included the concentration dependence of die swell and shear viscosity for the two solutions of hydroxypropyl cellulose (HPC) in dimethylacetamide and in dimethylsulfoxide.The die swell for both the systems exhibits a maximum and a minimum with respect to polymer concentration. The concentration at the maximum or the minimum is almost identical to that for the shear viscosity. A first normal stress difference N1 was converted from the die swell data on the basis of the theory which has been applied successfully to isotropic solutions and melts. The concentration dependence of the N1 converted is qualitatively similar to that reported by other investigators. The values of the die swell for lyotropic liquid crystals may be not so low as those for thermotorpic liquid crystals. This phenomenon may be attributed to the difference of a relaxation time between them.