The disclosure provides a transfer plate pre-processing device. The transfer plate comprises first and second surfaces, and recesses in an array are arranged on the first surface. The transfer plate pre-processing device comprises: a cylinder having a bearing surface that can be attached to the second surface of the transfer plate and to support the transfer plate; and a pressurization structure having a pressurizing surface. The cylinder can roll along the pressurizing surface, and when the cylinder is rolling, the first surface of the transfer plate is brought into contact with and pressed against pressurizing surface. Accordingly, the disclosure also provides a transfer plate pre-processing method and an alignment film preparation system. According the disclosure, the wettability of the transfer plate can be improved.