Abstract: In order to improve the passenger's experience in on-line ticket purchase and to reduce the occurrences of surplus tickets troubles, the causes of surplus tickets troubles are analyzed and a portfolio of technical solutions to assure the data consistency of surplus tickets in 12306 Internet ticketing and reservation system is proposed by combining several technical solutions including enhanced link monitoring of surplus tickets data synchronization, detection and repair of data inconsistency of surplus tickets, validation of surplus tickets calculation rules, dynamic adjustment of cache aging duration and so on. This portfolio was implemented in Dec, 2019 and its effect is evaluated by using the rate of customer complaints on surplus tickets troubles. The statistics shows that the customer complaint rate had been reduced by 80% after the implementation of this portfolio.