This paper discussed the sustainable development principle that planning should follow in the perspective of concept and content of ecological planning of urban landscape and then introduced complexity theory into research on ecological planning of urban landscape. Relative to “theory in planning” and “theory of planning”, complexity of ecological planning of urban landscape is divided into “complexity of planning” and “complexity in planning”. For “complexity of planning”, uncertain research method was introduced, and concept of “flexible planning” was proposed including flexibility of planning objective and flexibility of planning scheme. Planning objective and planning scheme for urban landscape were uncertain to make them be more operable. Research on urban landscape pattern that adapts to economic pattern will become the main trend of ecological planning of urban landscape in the future when looking into the future direction of ecological planning of urban landscape.