AbstractThe objective of research is determined the virulence of different concentrations of SlNPV-JTM 97C with kaolin as carrier material onS. litura and T. laevicepsmortalityon soybean. The Research was conducted in Plant Protection Laboratory of State polytechnic of Jember, from June to September 2020. The lethal concentration (LC50and LC95) SlNPVusing Polo Plus 1.0, with the IRAC version 3, method number 008. TheS. lituramortality test used Completely Randomind Design with 5 treatments and 3 replications. The treatments were contamination of larvae diet by SlNPV with control (the third instar larvae without contamination SlNPV), 0,1%, 0,2%, 0,3% and 0,5%. These concentrations are equivalent to the concentrations of 0.1.2x 108PIBs/g, 2.4x 108PIBs/g, 3.6 x 108PIBs/g and 6.0 x 108PIBs/g, respectively. Each test was repeated three times. Mortality percentage of larvae were observed as experiment data. Those data were analyzed by Analysis of Variant and Least Significant Difference (LSD) 5%. SlNPV virulence test againstT. laevicepsusing a concentration that can causeS. lituramortality ≥ 70%. The results of the research indicated that LC50of SlNPV with kaolin as carrier againstS. litura3rdinstar was 0.2%, LC95was 0.5%, effective concentration of SlNPV to controlS. litura3rdinstar was 0.3% to 0.5%, SlNPV concentration at 0.3% to 0.5%, non-toxic toT. laeviceps.