Sedimentary facies types,sedimentary characteristics and distribution law of Nantun group of Cretacic in Huhehu depression are analyzed on the base of core, well log curve, analysis assay, seismic and so on. The research indicated that Nantun Group developed fan delta, braided river delta, sublacustrine fan. This paper expounds in detail sedimentary characteristics and identification mark of fan delta, braided river delta and sublacustrine fan in cause, source supply, development position, sedimentary characteristics and seismic reflection characteristic. Fan delta mainly distributed in northwest gentle slope zone and southeast steep slope zone of Nanyi section; braided river delta mainly distributed in Naner section and north slope zone of Nanyi section; sublacustrine fan developed in deep lake-half deep lake facies . This paper pointed out that south sedimentary sand of Huhehu depression was the favorable exploration region at last, in which fan delta and braided river delta front subphase zone was the important hydrocarbon accumulation.