The　grain　boundary　character　distributions　of　sigma2　and　sigma13　boundaries　were　investigated　in　cemented　carbide　samples　with　different　carbide　grain　sizes.　Samples　were　prepared　with　average　carbide　grain　sizes　of　about　0.5　mu　m,　1　mu　m　and　2　mu　m,　respectively.　The　electron　backscattered　diffraction　measurements　show　that　with　the　increase　of　the　carbide　grain　size,　populations　of　both　sigma2　and　sigma13　boundaries　decrease;　in　the　meantime,　the　sigma2　twist　and　sigma13　twist　boundaries　keep　as　the　most　common　boundary　types.　The　results　suggest　that　the　carbide　grain　size　could　be　determinant　in　controlling　the　populations　of　coincidence　site　lattice　boundaries　in　WC-Co　composites.　(C)　2013　Elsevier　B.V.　All　rights　reserved.