Abstract: Based on the experimental data of boiling heat transfer in narrow rectangular channel with a cross section of 40 mm×2 mm, the main factors that impact the position of fully developed boiling (FDB) and boiling heat transfer coefficient were analyzed, then the experimental data and the calculated values were compared. The position of FDB obtained by experiment agrees well with the value predicted by Bowring correlation and Saha-Zuber correlation, and the relative deviation is within 20%. The boiling heat transfer coefficient acquired by experiment in narrow rectangular channel was compared with Chen correlation, Gungor-Winterton correlation and Sun Licheng correlation. The results indicate that the Chen correlation applied to conventional channel is not suitable for predicting the boiling heat transfer coefficient in narrow rectangular channel. While the Sun Licheng correlation considering the effect of narrow channel size and regarding the heat flux as the main function in boiling heat transfer can predict the experimental results well, and the relative deviation of the correlation and experiment is within 30%.