Abstract Mixed deposits, which is composed of terrigenous fragment and carbonate of marine facies, develops extensively in Cambrian around Bohai sea basin. Synthesized he previous studies, On the basis of studying the abundant outcrops and the data count to observe detailedly and interior data sample, carried out detailed research on the mixed deposits of the study area. In the study area, the macroscopic characteristics of mixed deposits are interbeded between terrigenous fragment and the mixed sediments , between carbonates and the mixed sediments, between different type mixed sediments in high frequency; the microcosmic characteristics of mixed deposits are showed the form of the mixed rocks ,which is composed of terrigenous fragment constituent and carbonate constituent of one layer. Mixed sedimentary type could be divided into 3 categories,blended mixed sedimentation, salutatory mixed sedimentation and complex mixed sedimentationⅠ, which is often effected by the deposition.,could be built up complex superposed geologic body. The study area sendimentary was ancient land fringe and epicontinental seaenvironment, there were sedimentary facies of mixed tidal flat,mixed restricted platform,mixed open platform,and sedimentary tiny facies of mixed mud flat,mixed limestone flat,mixed dolomite plat,mixed lagoon and mixed shallow,etc.In virtue of the analysis the cause of the mixed sedimentation, deposition mechanism, location developing, deposition environment, etc, being guided by study of deposition principles, the mixed sedimentary facies model was established.