To reveal the uncertainty of the travel behaviors of passengers living along the subway line after the subway operation disruption, the travel behaviors of subway passengers influenced by the incident were studied based on the cumulative prospect theory (CPT). According to the duration and influence range of the incident, there were 6 kinds of incident situations and 5 kinds of decision-making behaviors were proposed. Taking the weighted value of travel time and expense as the reference, the calculation formulas of travel cost of 5 kinds of decision-making behaviors were deduced. Taking Shanghai Metro Line 5 as an example, the actual travel time, expense and probability of each behavior were gotten through the field investigation, and the cumulative prospect values of travel behaviors with different travel purposes for 6 kinds of incident situations were calculated. The study results show that there are great differences in passengers' travel choices at different incident situations, and the purpose of travel is an important factor influencing their decision-making. Moreover, regular public transport and online car-hailing service become the preferred modes of travel when the incident lasts longer than 1.5 h and the influence range is large. The actual selections of passengers are consistent with the CPT analysis results, and the model based on CPT can better analyze the passengers' travel choices with the influence of the incident. Finally, scientific countermeasures are given to alleviate the negative effects of the incident.