The invention discloses a travel time index entropy traffic circulation evaluation method which comprises the following steps of a, calculating the free stream speed of each road section in a road network according to historical speed data provided by road network vehicle detection equipment, b, calculating the travel time index of each road section, c, calculating cut-off positions of the travel time indexes according to a quantile method or road capacity, d, calculating discrete probability distribution of the travel time indexes of a probe vehicle, e, calculating the entropy of the travel time indexes, f, calculating the highest possible value of the entropy as the upper limit of a dynamic range through the maximum entropy theorem, g, using the minimum entropy value Hmin of the travel time indexes as the lower limit of the dynamic range of the entropy of the travel time indexes, and h, carrying out normalization processing between the upper limit and the lower limit of the dynamic range of the entropy to obtain a road network traffic circulation evaluation value. The travel time index entropy traffic circulation evaluation method is a scientific characterization method of traffic circulation states, and measurement of traffic jam severity degree is achieved from the aspects of system confusion and randomness and uncertainty of travel time.