Abstract: The computational fluid dynamics(CFD) evaluation method was applied for (analyzing) effect of shores on thermal performance in narrow channel. The related numerical simulations of coolant flow in narrow channel with and without shores were performed (using) the CFD code——CFX. The coolant cooling ability of channel was predicted by comparing the relative peak spot temperatures around exit of the heating wall at the same heat flux condition. The results show that the shores have certain effects on critical heat flux of channel, but the effect is rather small as a whole. So they might be adopted in the test.