建设长江上游生态屏障是西部大开发的重要战略内容和目标之一，也是建立全国生态安全体系的重要组成部份。但是，长江上游生态屏障的恰切涵义是什么？建设的目标和评价体系与标准是什么？并没有科学的界定。因此，以政治口与代替科学决策的现象较为普遍。当前，在建设长江上游生态屏障中，有些概念和内容需要澄清：（1）“山川秀美”与生态屏障。对山川秀美需加以科学界定，否则易得出喀斯特地区早就已建成生态屏障的结论。（2）森林覆盖率达到40%以上，就等于建成生态屏障。忽略了生态系统的及其功能的复杂性、多样性。（3）生态屏障与减少泥沙进三峡库区，过于强调减少泥沙的功能和速效。理解过于狭窄，实际上也做不到。（4）生态屏障建设5年就能初见成效，10年就能大见成效，30年就能建成。低估了生态屏障建设的长期性、艰巨性。（5）建设成生态屏障，就能消灾保平安。对自然灾变过程与人地矛盾，缺乏正确的理解。为切实搞好长江上游生态屏障建设，应首先明确生态屏障的建设目标，评价体系和评价标准；并在此基础上，对长江上游进行全面系统的生态区划和生态建设规划，划分不同生态类型区，明确各生态类型区在长江上游生态屏障建设中的地位、功能、建设标准；因地制宜，避免一刀切；要树立系统、综合、全局观点，反对部门、地区割据；要树立长期奋斗艰苦观点，反对浮夸和短期行为；要建设起生态屏障的社会、经济支撑体系和科学的管理体系。

 What constructing the ecological defence in the upper Reaches of the Yangtze Basin is not only one of important strategical contents and goals of Western development, but also a significant part of ecological system of national security. But what is the exact definition of ecological defence? What is its goal, evaluation system and standard? All of them are not given a scientific answer untill now. The instances that political slogans substitute for scientific decision～making often appeared. At present, it exists several misunderstandings for constructing the ecological defence of the upper Reaches of the Yangtze Basin: (1)misunderstand "Landscape beautiful" equates the success of ecological defence construction. The regions of karst would have been succeeded earlier if according to this understanding. (2)that the percentage of forest cover is over 40% indicats building up ecological defence. This grasp ignores their complication and diversity of ecological system. (3)the thinking that ecological defence construction means to deduce silt depositing in the Three Gorges Reservoir and prevent flood happening like that in 1998, is a narrow～minded and falling in practice. (4)many regional plannings of ecological defence said that they would get primary success in 5 years, get big success in 10 years and get full success in 30 years. They understimate the difficulties for constructing ecological defence. (5)no hazards and eternal security when ecological defence constructs completion, it lacks to understand the complecation of natural change process and the relation between man and the earth. For constructing ecological defence of the upper Reaches of the Yangtze Basin better, firstly we should make sure the goal, evaluation system and stardand of the construction. And follow this, we should give a systemic and overall ecological regionalization and a ecological construction planning for the upper Reaches, divide Various regions of ecological types and dearly and fully express its role, function and construction stardand in ecological defence of the upper Reaches. It would keep in mind to take the measures suitable to local conditions, against uniformity imposed. So it is nacessary to insist on a systemic, integrated and overall viewpoint for opposing separationists between different regions and between different departments. We should set up the idea of long, hard and arduous struggle and fight against boast and short～seeing behavior. More important thing is do our best to set up a social and economic supporting system and scientific administrating system for the construction of ecological defence.