To provide a congestion information control device and a congestion information display system which can display an accurate congestion state of polls in real time.

In the congestion information control device, a service time measurement section 31 of a voting terminal 9 measures a service time T2 in each time T1 for a service monitoring period T1 of time, an operation ratio calculation section 33 calculates an operation ratio T, a congestion information control device 5 acquires the operation ratio T of the voting terminals 9 of each of polls through a host system 3, a congestion data computation section 43 computes an average operation ratio of the voting terminals of each of the polls, a display data creation section 45 creates congestion state data 100 based on the average operation ratio, creates congestion display data based on the created congestion state data 100 and transmits the created congestion display data to a display panel 13 or the like provided in each of the polls, and the display panel 13 or the like displays the congestion display data.