The choice theory derived from decision analysis is the foundation for microeconomic theory .With the emergence of complexity science and cognitive psychology,the economic choice theory based on subjective expected utility (SEU) is being challenged . Faced with the complex,uncertain real world,the traditional myopicchoice theoryis insufficient and should be substituted with the theory of plan-based actions . Different from the choice theory that focuses on making single decisions independently,the theory of plan-based actions considers more than one interdependent decision at a time in order to deal with complexity in the real world . When decisions are interdependent,indivisible,irreversible,and imperfectly foresighted,plans are more effective than decisions . For these reasons,it is necessary for us to explore into planning behavior in a systematic way to construct a behavioral planning theory . The research methods adopted include axiomatization,psychological experiments,and computer simulations . Only when we gain a better understanding of the logicof making plans are we able to better achieve the goals in the complex environment and survive .