Provided is a settlement terminal device including a plurality of information processing units. The settlement terminal device includes a first information processing unit, a secure second information processing unit, and an orientation detection unit which detects a direction of the settlement terminal device with respect to gravity. The first information processing unit reflects a detection result of the orientation detection unit on an orientation of a first display content displayed on the first display unit, and the second information processing unit determines whether or not to reflect the detection result of the orientation detection unit on an orientation of a second display content, in accordance with the second display content displayed on the second display unit. Thereby, a settlement terminal device capable of easily performing an input operation and display confirmation in a settlement process is provided.