Abstract: To study the effects of suppression of the E1A gene in tumors in nude mic that arise after injection of human cervical carcinoma HeLa cells and the related mechanism of action. Methods: Immunohistochemical staining was used to detect the effect of the E1A gene (by PEI-Fe3O4NP mediation and transfection) on expression of survivin and caspase- 3 and to observe apoptosis of the tumor cells. Results: The results showed that tumors arising from the Hela- E1A cells occurred much later compared to those arising from the Hela and Hela- vector cells. Hela- E1A cells also displayed slow growth and low tumor volume. The tumor control rates were 83.42% and 84.74%. Results of immunohistochemistry staining showed that the apoptosis rate of the Hela- E1A cells was significantly higher than that of the Hela and Hela-vector cells. Caspase-3, a pro- apoptotic gene, displayed increased expression, and survivin, an anti- apoptotic gene, showed decreased expression. Conclusions: The E1A gene can effectively inhibit cervical carcinoma tumor growth in nude mice and the mechanism may relate to the E1A- induced increased expression of the caspase- 3 gene and the decreased expression of the survivin gene.