With the research of the upcoming sixth generation(6G)systems,new technologies will re-quire wider bandwidth,larger scale antenna arrays and more diverse wireless communication scenarios on the future channel modeling.Considering chan-nel model is prerequisite for system design and per-formance evaluation of 6G technologies,we face a challenging task:how to accurately and efficiently model 6G channel for various scenarios?This paper tries to answer it.Firstly,the features of cluster-nuclei(CN)and principle of cluster-nuclei based channel model(CNCM)are introduced.Then,a novel mod-eling framework is proposed to implement CNCM,which consists four steps:propagation environment reconstruction,cluster-nuclei identification,multipath parameters generation,and channel coefficients gen-eration.Three-dimensional environment with mate-rial information is utilized to map CN with scatter-ers in the propagation pathway.CN are identified by geometrical and electric field calculation based on environmental mapping,and multipath components within CN are calculated by statistical characteris-tics of angle,power and delay domains.Finally,we present a three-level verification structure to investi-gate the accuracy and complexity of channel model-ing comprehensively.Simulation results reveal that CNCM can perform higher accuracy than geometry-based stochastic model while lower complexity com-pared with ray-tracing model for practical propagation environment.