As a type of unearthed documents, inscriptions are important materials for the study of ancient languages, history, and culture. Characters of popular forms are the supplement and reserve force of the orthographic system. Following the trend of the Han, Wei and Six Dynasties, the characters of popular forms in the Northern Zhou and Sui dynasties are still complex, which is a valuable material for the study of Chinese character history. It is the variety of styles and strange shapes that make it difficult to interpret the stele inscriptions during this period, and the collections of the inscriptions often misinterpret the characters of popular forms. This paper selects twelve characters of popular forms among them and corrects with evidence their faulty interpretation, providing reference for the study of modern Chinese characters and the history of Chinese characters.