A point-of-sale system with a replaceable printer is provided. The point-of-sale system includes a main body and the printer. The main body is electrically connected with a display device. The main body includes a main circuit board, an accommodation member and a positioning structure. The printer includes a detaching element and a position-limiting element, which are connected with each other. The printer is disposed within the accommodation member of the main body and electrically connected with the main circuit board. The position-limiting element of the printer is aligned with the positioning structure of the main body to limit the position of the printer in the accommodation member of the main body. The printer is detached from the main body through the detaching element. Consequently, the printer can be easily detached from the main body through a single keypress action.