Abstract: A Study on the distributive patterns of Mathmatical Mode of Probability of He-morrhagic Fever with Renal Syndrome(HFRS) was carried out in Menyin county 1994.There-sults indicated that the distribution of HFRS was not accorded with the Poisson distrioution,but accorded with the Negative binomial distribution.It suggested that there was a cluster in case dis-tribution.The study on the case distribution among the distants from the center of villages of theside of villages to theriver was also calculated by using the rank sum test.The result showed that the most cases were concentrated in the side of villages closed to the river.