Abstract: The rapid development of inter- and transdisciplinary research has given many challenges to the related grant and management mechanism. Behind the contradiction and disagreement is the deferent understanding of key five key issues about inter- and transdisciplinary research. Based on the literature review, through summarizing the main findings about the definition and concept, the purposes, key success factors and the grant and evaluation of inter- and transdisciplinary research, the paper finds that integration is the key element of inter- and transdisciplinary research, the grant aim of which should be advancing the effective integration to promote the development of inter/transdisciplinary research.