SummaryAs a burning issue in today's society, the study on information spreading has great theoretic and practical implications. After analyzing the dynamics of information spreading, characteristics of decrease progressively probability and step change property have been disclosed. Taking these into account, the variable probability Known/Unknown (VPKU) model for information spreading is built with appropriate parameter assumption. Then, simulation experiments are made to evolve the VPKU model and analyze the regularity of information spreading. Furthermore, applying the VPKU model, the control strategy of information spreading is proposed and discussed. Simulation and analysis shows that the VPKU model can reflect the process of information spreading in different situations with different parameter setting.