The driving force of scientific and technological innovation has become the leading factor for the high-quality development of the Yangtze River economic belt. Based on the system framework of scientific and technological innovation driving force based on input-output carrier performance，this paper constructs an index system to quantitatively evaluate the scientific and technological innovation driving force and its internal coupling and coordinated development of 110 cities in the Yangtze River economic belt. The results show that the comprehensive driving force of scientific and technological innovation in the cities of the Yangtze River Economic Belt presents a pyramid hierarchical structure，with the characteristics of gradient spatial differentiation in the upper reaches＜the middle reaches＜the lower reaches；There are similar spatial distribution characteristics between input driving force and comprehensive driving force. The agglomeration of output and carrier driving force is stronger than input driving force，and the spatial distribution of performance driving force is relatively balanced；The coupling and coordination within the driving force system of scientific and technological innovation in the Yangtze River economic belt is generally low，but the coupling and coordination degree of cities with strong comprehensive driving force of scientific and technological innovation is relatively better，and the driving force of scientific and technological innovation has a polarization trend. Compared with the previous research results，in general，the driving force of scientific and technological innovation in cities in the Yangtze River economic belt is constantly improving. Cities with strong comprehensive driving force of scientific and technological innovation are constantly making up for their shortcomings，so they should give greater play to their comprehensive advantages and play a leading role in collaborative innovation；The comprehensive driving force of scientific and technological innovation is weak，and cities are also accumulating strength to forge long plates，which may lead to the decline of coupling and coordination within the urban scientific and technological innovation driving force system. However，as a whole，from the perspective of the Yangtze River economic belt，small and medium-sized cities should focus on local advantages，create distinctive scientific and technological innovation forces，and actively participate in regional collaborative innovation，so as to solve the problem of imperfect internal system.