CANDLE (constant axial shape of neutron flux, nuclide densities and power shape during life of energy producing reactor) burnupstrategy is applied to small (30 MWth) block-type high temperature gas-cooled reactors (HTGRs) with thorium fuel. The CANDLE burnupis adopted in this study since it has several promising merits such as simple and safe reactor operation, and the ease of designing along life reactor core. Burnup performances of thorium fuel (233U, 232Th)O2 are investigated for a range of enrichment 615%. Dischargedfuel burnup and burning region motion velocity are major parameters of its performances in this study. The reactors with thoriumfuel show a better burnup performance in terms of higher discharged fuel burnup and slower burning region motion velocity (longercore lifetime) compared to the reactors with uranium fuel.