The effect of anticancer drugs could be significantly enhanced if it is encapsulated in drug delivery vehicles such as liposomes, polymers, dendrimers and other materials. For some conventional cisplatin encapsulating methods, however, suffers from low loading efficiency. Therefore, in order to overcome this limitation, in our study, sonication was used in preparation of the nanocomplex of a species of aquated cisplatin and carboxylated PAMAM dendrimer G3.5 to evaluate loading capacity as well as plantinum release behavior using FT-IR, UV-Vis, NMR, ICP-AES, and TEM. The results show that 25.20 and 27.83 wt/wt% of cisplatin were loaded under stirring and sonication respectively, a remarkably improvement in loading efficiency compared to that of conventional method that used of cisplatin. In vitro study showed that this drug-nanocarrier complex also help reduce cisplatin's cytotoxicity but can still keep sufficient antiproliferative activity against lung cancer cell, NCI-H460, with IC50 at 0.985 ± 0.01 μM.