Abstract: The steam generator in China Experimental Fast Reactor (CEFR) is direct flow type, and the steam generator startup of CEFR is quite different and more complicated than that of PWR. In this paper, the startup condition of steam generator was studied, and the operation parameters were compared with theoretical design parameters. The results show that the calculated theoretical value of operation parameters is basically coincident with test value. The optimized startup program of steam generator for guiding operator was also introduced. The optimized procedure to start up the steam generator is proposed for guiding operators, and it effectively ensures the power operation test of CEFR.