Abstract: The annular fuel zero power reactor is the first reactor to use double-sided moderator annular fuel as nuclear fuel. In this research, the period method and the drop rod method were used to obtain the critical parameters of the annular fuel zero power reactor, the worth of the control rod, the fuel cell worth, the reactivity effect of the Gd-containing cell and other critical parameters. The physical performance of the annular fuel zero power reactor was experimentally studied, which verified the core physical code for the annular fuel reactor. The results show that the core is loaded with 96 annular fuel cells and 172 solid fuel cells according to the extrapolation critical process. At this time, the k_eff is 1.000 40, the worth of the regulating rod is -247.5 pcm, and the worth of the safety rod is -1 358.4 pcm. The average deviation of the fuel cell from the theoretical worth is 1.3 pcm, and the average deviation of the Gd-containing cell reactivity effect from the theoretical worth is 8.8%. These experimental data provide critical data support for the annular fuel core physical engineering design code.