Abstract: The invention concerns an electrochromic glazing system, with an electrochromic pane unit and at least one other pane, which are joined to one another in the edge area by means of a spacer frame, forming an interspace, and with a temperature sensor for detection of the temperature of the electrochromic pane unit. To optimize its location, according to the invention the temperature sensor is arranged in the region of the spacer frame, between the electrochromic pane unit and the other pane. The invention takes advantage of the fact that the spacer frame area represents a thermal bridge between the panes of a double-glazing unit which is especially suitable for the arrangement of a temperature sensor.