FRC post has been commonly cemented by resin cement, but there is not adhesive with tooth structure. Cement that has adhesive system with tooth structure is glass ionomer cement. Glass ionomer cement (GIC) cannot be adhesive with FRC post without silane coupling agent. The aim of research was to know influence silane level to tensile strength of E-glass FRC post (cementing with GIC). This research used 20 first mandibula premolar teeth. We divided into 4 groups. Group A, FRC post without silane application; group B, with silane 1% application; group C, with silane 2% application; group D with silane 3% application. All FRC post were cemented by GIC. Tensile strength was tested by Torsee’s digital system universal testing machine. Data was analyzed by anova and LSD. The following tensile strength values were obtained: group A: 0.14 + 0.003 MPa; group B: 0.35 + 0.0094 MPa; group C: 0.71 + 0.0055 MPa; group D: 1.43 + 0.22 MPa. The result of anova test showed that there were significant differences between silane level. The LSD test showed significant difference between mean groups. We concluded that silane level influence to tensile strength of E-glass FRC post prefabricated with GIC as luting cement.