Abstract: A seat reservation device (100) includes: a pattern extraction unit (103) to extract, from a consecutive-seating pattern candidate group (240A), a consecutive-seating pattern group, based on train reservation information (210) and train vehicle information (220); a reservation totaling unit (104) to total counts of suites per suite type having a same boarding section and a same same-time reservation people count, from the reservation information (210), and to generate total information (250); a problem generation unit (105) to generate an optimization problem (260) on seating layout of reservation passengers, which involves a decision variable not dependent on a reservation people count, a constraint condition, and an objective function, based on the vehicle information (220), an evaluation index, the consecutive-seating pattern group (240B), and the total information (250); a solution unit (106) to solve the optimization problem (260) and to decide the seating layout (270) of the reservation passengers.