Abnormality of fibroblast growth factor receptors (FGFRs) mediated signaling pathways were frequently found in various human malignancies, making FGFRs hot targets for cancer treatment. To address the consistent need of new chemotype of FGFR inhibitors, here, we started with a hit structure identified from our internal c-Met inhibitor project, and conducted a chemical optimization. After exploring three parts of the hit compound, we finally discovered a new series of pyrrolo[2,3-b] pyrazine FGFR inhibitors, which contain a novel scaffold and unique molecular shape. We believed that our findings can benefit others to further develop selective FGFR inhibitors.