In order to improve the performance of treating waste-water with wastes, the magnetic fly ash (FA) particles were surface-modified with polymerizable groups as the crosslinker for the copolymerization with acrylic acid (AA) and acrylamide (AM) by a facile inverse suspension polymerization process, without any foreign organic crosslinker added. The optimized beadlike magnetic fly ash/poly(acrylic acid-co-acrylamide) composite microgels (FA/P(AA-AM)) with 3-dimensional crosslinking skeleton structure were selected as the magnetic selective microgel adsorbent for Pb2+ ion, through a series of L-9(3(4)) orthogonal experiments. It was found that the magnetic FA particles could improve the strength stability of the FA/P(AA-AM) composite microgels, also provide the ability of magnetic separation. (C) 2014 Elsevier Inc. All rights reserved.