本文根據漢語方言研究的經驗，討論三項問題：（一）漢語方言學和印歐語言學在語言層次研究旨趣上的異同；（二）漢語方言層次辨認的方法及其限度；（三）利用層次變體動建原始語言應留意的要點。語言層次的研究，是近數十年來漢語方言學中最受關切的課題之一。本文討論其中與方法學相關得若干問題，希望能對語言史的研究有所助益。

　　　　　Three problems relating to linguistic strata are discussed in this article: (1) the differences in main concerns between Western and Chinese linguistic traditions in the study of linguistic strata; (2) the methods of identifying linguistic strata; (3) the methods for reconstructing protolanguages by using evidence from linguistic strata. Examples from Min dialects are given in the discussion.