Lobaplatin, as the third-generation platinum antineoplastic agent, showed promising antineoplastic effects in variety of preclinical test tumor models. We investigated the inhibition effect of lobaplatin on the colorectal carcinoma cell line LOVO in vitro, and explored its mechanism of action. The MTT assay was used to determine the inhibitory effect and inhibition ratio of lobaplatin on LOVO at various lobaplatin concentrations (500μM, 1000μM, 2000μM). Apoptosis was detected by terminal deoxynucleotide transferase-mediated dUTP nickend labelling (TUNEL). The cell cycle and apoptotic rate were analyzed by flow cytometry (FCM) and the expression of caspase-3,8,9 in cells was detected by chromometry. The results of MTT assay showed that proliferation of LOVO cells was inhibited by lobaplatin in a concentration-dependent manner. Apoptosis was detected in LOVO cells by TUNEL. The FCM assay indicated that lobaplatin altered the cell cycle and induced apoptosis of the LOVO cells when treated for 24h, the percentages of cells in the S phase transition were increased, whereas the percentages of cells in the G₂ transition were decreased. The expressions of caspase-389 is higher than the control group after LOVO cells were treated by lobaplatin. Lobaplatin can inhibit the proliferation of colorectal carcinoma cell line LOVO by inducing apoptosis in vitro. The mechanism may be related to the “S” cycle arrest in cell cycle distribution and the up-regulated expression of caspase-8 and caspase-9 which up-regulated the expression of caspase-3.