AbstractWaxy maize contains nearly 100% of the branched amylopectin type of starch, which has a similar structure to that of a commercial anionic organic micro-particle (OMP). It was found that the maize starch would have the same function as the OMP if carboxymethyl groups were introduced; moreover, the performance of carboxymethyl starch as a retention and drainage aid could be enhanced by grafting some cationic groups on the backbone of the starch so that it could absorb on fibers through electrostatic attraction. In this study, the introduced groups of cationic-modified carboxymethyl starch (CCMS) prepared from waxy maize were determined by FT-IR and 1H NMR spectroscopy. Factors affecting retention and drainage, comparison between CCMS and OMP systems, and also the strengthening effect of CCMS were studied. The results showed that CCMS had excellent performance when it was used with cationic polyacrylamide (CPAM) as a retention system. Compared with the OMP, CCMS had better retention performance when the dosage was in the range from 0.01% to 0.08%, and it yielded much more uniform formation of the handsheets. Additionally, CCMS had a strengthening effect on the paper, which distinguished it from other retention aids.