Two data analysis programs of Sedfit and VelXLAI associated with analytical ultracentrifugation were compared with each other for the sedimentation analysis of a pure polystyrene polymer solution as well as solutions of polymer mixtures in organic solvent containing two components in different mixing ratios. Interference detection optics was used for the sedimentation analysis. The pure polymer showed concentration dependency of the sedimentation coefficient and the results were similar in both the programs. In the mixture samples, slight differences in the peak sedimentation coefficients of the two polymers fractions in the analysis programs were observed. However, VelXLAI program was observed to detect the relative fractions of the two mixture components more accurately than Sedfit.