Abstract: Objective To explore middle molecular substances (MMS) and parathyroid hormone (PTH) removal performance differences on uremic patients of activated carbon and several resin adsorbent. Methods Maintenance hemodialysis patients’ blood were randomly divided into four groups，respectively for AC（activated carbon）、MR1、MR2、MR3（resin）by adsorption in vitro test. Detect blood MMS and PTH before and after adsorption，combined with the sorbent pore structure，to analyze MMS and PTH removal performance differences of activated carbon and resin. Results Within the same group the comparison of before and after adsorption，four groups of blood MMS，PTH level difference has statistics significance(P MR2> MR3 > AC，four group difference has statistics significance (P<0.05). Conclusions Due to wider pore size distribution range，activated carbon is more favorable on removing the middle molecule substances；resin having relatively centralized pore size distribution，removal for the single molecule toxins such as PTH is more favorable.

Key words: Activated carbon, Macroporous adsorption resin, Middle molecular substances, Parathyroid hormone