Due to dynamic changes of an environment and various kinds of uncertainties in a real world, mobile robot localization is difficult to be solved by a single continuous algorithm. In order to achieve a practical localization solution generally, this paper proposes a strategy to deal with various uncertainties using explicit discretization of robot's status. Discrete status of localization is designed with three criteria as follows: (i) polygonal environment and non-polygonal environment, (ii) static environment and dynamic environment, and (iii) global positioning problem and local tracking problem are defined. An appropriate strategy is adopted according to the robot's status. The feasibility of the proposed method is demonstrated by simulation results.