Collaborative　innovation　is　the　key　support　for　promoting　high-quality　regional　development.　Taking　Guangdong,　Fujian　and　Zhejiang　coastal　city　clusters　as　an　example,　this　paper　analyzes　the　evolution　mechanism　of　collaborative　innovation　network　based　on　the　＇two-wheel　drive＇　perspective　of　external　proximity　and　endogenous　gravity.　The　results　show　that　the　difference　of　resource　control　ability　among　nodes　in　the　network　is　decreasing,　and　the　inverted　＇V＇　structure　with　Xiamen　and　Putian　as　the　main　apex　has　evolved　into　a　more　robust　＇dual　core＇　(Fuzhou-Xiamen)　radiation-type　spatial　structure.　In　addition,　the　evolution　of　regional　collaborative　innovation　network　is　driven　by　＇two　wheels＇.　In　external　proximity,　institutional　proximity　plays　the　strongest　role　in　promoting,　followed　by　geographical　proximity,　and　the　promoting　role　of　technological　proximity　is　gradually　weakened.　In　the　endogenous　gravity,　the　influence　of　investment　in　science　and　education　is　strengthening,　while　the　influence　of　the　administrative　level　is　declining.