Survivin is expressed in most cancers but is undetectable in differentiated adult cells, and plays an important role both in the suppression of apoptosis and mitotic spindle checkpoint; thus it has attracted great interest as a potential drug target. In this study, we investigated the antigene and antiproliferative effects of triplex-forming oligodeoxynucleotides (TFO) targeting survivin in human lung carcinoma A549 cells. Survivin-specific TFOs form stable triplexes under physiological conditions as tested by electrophoretic mobility shift assays. Treatment of A549 cells with survivin-specific but not control TFOs at a concentration of 400 nM in the presence of uptake-enhancing liposome significantly reduced survivin protein level, inhibited cell proliferation, and induced cell apoptosis as demonstrated by immunoblot, cell number counting, and Annexin V-staining. Moreover, we found that the triplex-forming potential of TFOs measured in vitro does not necessarily correlate with the ability of TFOs to affect expression of a targeted gene in vivo. Our results indicate that targeting survivin is a promising alternative strategy for the development of novel anticancer therapeutics.