Abstract: Experimental investigation on flow resistance coefficient for the tight arrangement spiral-fin fuel assembly was performed. Results show that the inlet temperature has no effect on the flow resistance coefficient. The deviation between the proposed correlation and experimental data is less than 1%. A good comparison between Rehme correlation and experimental data was obtained when Reynolds number is small. Numerical simulation with BSL Reynolds stress turbulence model for the tight arrangement spiral-fin fuel assembly was carried out. Flow resistance coefficient,velocity distribution and secondary velocity were analyzed. The deviation is less than 8%. It shows that the CFD method could be used to predict the flow resistance coefficient for the tight arrangement spiral-fin fuel assembly.