选择灌溉保证率和设计年,是灌溉工程设计中首先遇到的、最根本的问题.目前常用的方法多少均存在一些缺陷,所得到的结果都不够理想.本文试就这个问题作一些探讨.在完成本文时曾蒙设计院徐恰时院长、冯世京副总工程师、陈绍沂工程师及浙江农业大学沈光史教授等提出宝贵意见,谨此志谢. Choosing irrigation guarantee rate and design year is the first and most fundamental problem encountered in irrigation engineering design.At present, there are some defects in the commonly used methods, and the results obtained are not ideal enough.This paper makes some discussions on this problem. At the completion of this article, Professor Xu Qiaoxi, Dean of Design Institute, Deputy Chief Engineer Feng Shijin, Professor Chen Shaoyi and Professor Shen Guangshi from Zhejiang Agricultural University made valuable suggestions.