Promising therapeutic application of RNA interference (RNAi) depends on the availability of safe and efficient intracellular delivery systems. Human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase complex, is an attractive therapeutic target for oral cancer. Here we investigated the characteristics and anticancer effect of polyamidoamine (PAMAM) dendrimer-mediated short hairpin RNA (shRNA) against hTERT in oral cancer. Dendrimer-mediated shRNA efficiently silenced the hTERT gene in vitro, resulted in cell growth inhibition and apoptosis. Treatment with the shRNA dendriplex attenuated tumor growth in a xenograft model. These studies suggest that RNAi-mediated hTERT gene silencing, coupled with dendrimer delivery, may provide a promising approach for the treatment of oral cancer, in which hTERT is abundantly expressed.