To recover water-soluble polydextrose of high purity by dissolving a mixture containing specified amts. of polyglucose, glucose, anhydroglucose, sorbitol and citric acid to a specified concn., passing the mixture soln. through a column containing a separation resin, and separating glucose or the like depending on the difference in distribution coeffts.

Columns are packed with an ionic resin adsorbent in a strong acid gel state, and a supply soln. 1 and desorption water 2 are continuously supplied to respective columns, and discharged and circulated while moving the positions to supply and discharge. A mixture containing polyglucose, glucose, anhydroglucose, sorbitol and citric acid by 75 to 95 wt.%, 2 to 10 wt.%, 2 to 10 wt.%, 1 to 5 wt.% and 0.5 to 3 wt.%, respectively, is dissolved in distilled water to obtain 45 to 55 wt.% conc. of a dried substance at 55 to 65°C. Each column is equipped with the entrance and the exit for this soln. and the desorption water at the top and bottom part. Glucose, anhydroglucose, sorbitol and/or citric acid are selectively separated to recover water-soluble polydextrose of high purity.