A complete replication of the #Sesamia cretica Granulovirus (ScGV) was obtained in vitro by viral infection, as a first record, in two #Spodoptera cell lines. Sl52 and Sf9. ScGV was multiplied in the two cell lines cultivated and established at 27°C after infection with concentrated purified virions used as inoculum. The presence of virus was detected by a DNA nucleic probe, confirming previous results detected by ELISA test. The observation of ultrathin sections of infected cells indicated that complete granules were present in the cell cytoplasm in a significant amount. Purified suspension of granules was obtained after ultracentrifugation on sucrose gradient. The biological characterization of ScGV was completed by in vitro replication. This important Granulovirus was already used by the authors for microbial control of #S. cretica$ larvae on maize. (Résumé d'auteur