Reasonable concessionprice is critical for the healthy and sustainable development of urban transportation infrastructure project (UTIP) under Publicprivate partnership (PPP) model.Instead of considering only the private investor’s interests, all stakeholders’ interests should be taken into consideration in the determination of concession price.Therefore, some influential factors for the concessionprice adjustment of UTIP under PPP model are selected and a concessionprice adjustment model applying GABP method is established, which is an improvement to the BP neural network method using genetic algorithms so as to make full use of their advantages of respective method.The relevant empirical research is carried out for a subway project in a city and with the conclusion that this new concessionprice adjustment model improves the precision of the result of calculation and therefore is more scientific, reasonable and feasible.