The first member of Guanghua formation, developed in Taigu Mountain area, is a set of normal pyroclastic sedimentary rocks. Based on the rock association, fabrics, vertical variation and the changes of sedimentary environment of the area, one second-order sequence can be recognized, including 2 third-order sequences with 7 fourth-order sequences. The study on the sequence stratigraphy may support the research on the sequence strata of Mesozoic continental basin in Great Higgan Mountains region.