Abstract: Since the integrity policy model has been proposed, its maturity has always been lower than that of the confidentiality policy model. The restriction is due to integrity level dividing and usability. In this paper, different kinds of integrity models are summarized from the point of practicability with their characteristics concluded. Based on the previous discussion, this paper presents a practical dynamic integrity protection model called DMIP. It simplifies the intricacy of integrity level dividing and solves the existing problems on practicability of current integrity models especially for Linux. The DMIP is designed to preserve the integrity of system from potential network-based attacks and local malicious files. From the usability of Linux, DMIP improves the current integrity protection models. The paper also shows the invariant and constraint of DMIP model and provides formalization proof in theory.