Corydalis Rhizoma (Yanhusuo), is a very important Traditional Chinese Medicine used in clinical situations for pain relief. Its adulterants (Northeast Yanhusuo), which are also from Corydalis and distributed in the Northeast of China, are sometimes used instead of Corydalis Rhizoma. In this paper, we compared the chemical differences of Corydalis Rhizoma and its seven adulterants by HPLC-DAD-Q-TOF-MS associated with chemometric analysis. We identified 48 alkaloids, 14 of which are reported for the first time based on the Mass data. The classification of the different compounds was verified by Partial Least Squares Discriminant Analysis (PLS-DA) and Hierarchical Clustering Heatmap analysis based on 26 samples. We found significant differences in the categories and content of the alkaloids between different species. Corydalis yanhusuo (C.y.) is similar to Corydalis turtschaninovii (C.t.), which mainly contains protoberberine, tetrahydroprotoberberine and protopine types of alkaloids. Six other Northeast Yanhusuo, including Corydalis repens(C.r.), Corydalis watanabei (C.w.), Corydalis ambigua var. amurensis (C.a.) as well as its three forma, can be classified into one category, because they mainly contain benzophenanthridine and aprophine-type of alkaloids. © 2017 Elsevier B.V.