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It was described in the preceding paper that the recovery of actinoids were sometimes unsatisfactory. In this paper, some experiments on the recovery were carried out. Dependence of pH on adsorption (uptake) with glass fibre filter paper, influence of the presence of ammonium nitrate and calcium magnesium phosphate on the uptake were examined for uranium, neptunium, plutonium and americium. Centrifugation of the solution were also examined. In the case of solution containing calcium magnesium and phosphate, centrifugal experiments revealed that a very small amount of precipitate was formed at pH less than 5.0, and a close relation was found between precipitate formation and uptake or centrifuged out of the actinoids. As the results, it is thought that the actinoids are first coprecipitated with phosphate precipitate, then it is separated by the glass fibre filter paper. The amount of the precipitate may be influenced by the calcium magnesium contents in the sample, or by the conditions of the pH adjustment, and it has an effect on coprecipitation or counting efficiency of the actinoids. Consequently, it seems that some extents of the recovery fluctuation is unavoidable.