森林对于降水的影响是一个在科学界持续百余年的复杂问题，关于这种影响的错误分析，可能会导致指导思想的混乱与行动上的失误。因此，对这一问题的研究极具理论价值与实践意义。论文从对比观测、统计分析和模拟分析3种不同的研究方法入手，对有代表性的文献进行归纳整理，试图就这一复杂问题进行判断，得出一些初步认识。结果表明，不同的研究手段所得出的结论往往差距很大，其中存在着很大的主观性；各种研究方法均存在着某些需要改进的地方。更加深入的研究，不仅应考虑低层大气的物理变化，还应考虑植被的生物学特征，如林草的生理特征和生态适应性及土壤水分平衡问题，特别是随着植被覆盖的变化，植被的水分消耗、土壤水分的动态以及区域水资源的可能变化，而这些问题在区域生态恢复与建设中可能具有更加重要的意义。

 The problem of forest effects on regional precipitation is very complex which has been existing in the fields of forestry ecology， forestry meteorology and forestry hydrology for over one hundred years．Any wrong analytical result will lead to much confusion in ideology and misplay in practice． Therefore， the researches and disputes to the problem are significant in both theory and practice． Viewing from paralleling observations， statistical analysis and simulative modeling used in some typical literatures，the primary and qualitative results were obtained．The results show that there exist big differences between different research methods due to subjectivities in almost every method． The further search should not only be focused on the physical mechanisms of atmospheric boundary but also physiological and ecological characteristics of forests and grass and soil water balance as well．Especially，with the variations in vegetation coverage，water consumption of vegetation，dynamics of soil water，and possible changes of regional water resources should be paid more attention to，which is much more important in regional ecological restoration and construction．