Abstract: Based on the analyses in observational data, it is indicated that the precipitation in the flood period over Huabei area has low-frequency oscillations with different time scale. The quasibiennial period variation of precipitations is very obvious and it has close relations with QBO. The 16-year quasi-periodical variation of precipitations is also in existence. It has been found that the precipitations over Huabei area in summer has clear 30-60 day oscillation for the rainy years, while this oscillation is not obvious for the drought years. An important influence of ENSO on the precipitation in the flood period over Huabei area is investigated. In general, the precipitation in the flood period in El Ninño year is less than normal, but more in inverse El Ninño year. The anomalies of general circulation caused by El Ninño is a direct reason to produce anomalous variation of the precipitation. On other hand, the influences of general circulation in the high-latitude and pole area on the precipitation in the flood period over Huabei are discussed in this paper.