Silicalite-1/titanium silicalite-1 (TS-1) composites were synthesized by growing silicalite-1 on the surface of TS-1. Oxidation of 1-hexene was studied using both the silicalite-1/TS-1 composite and uncoated TS-1. The silicalite-1/TS-1 composite showed a higher selectivity toward 1,2-epoxyhexane than uncoated TS-1 because sequential reactions on the external surface of TS-1 were inhibited. The catalytic activity of the silicalite-1/TS-1 composite was almost the same as that of TS-1, suggesting that the silicalite-1 layer is very thin and that the diffusion resistance is negligibly small.