The present disclosure disclosed a display information processing device and method suitable for a host system, the method comprises: determining whether specification of interfaces of a plurality of extended display devices connected to extension interfaces conforms to the default specification of interfaces of the host system; calling drivers corresponding to a plurality of extended display devices from the host system to drive the plurality of extended display devices with the specification of interfaces conforming to the default specification of interfaces of the host system; obtaining resolution information from the plurality of extended display devices, respectively; determining a common resolution from the resolution information of the plurality of extended display devices; and outputting display information of a main display device to the plurality of extended display devices based on the common resolution. The present disclosure solves the issue of installing drivers and fix the problem of unsupportive resolution of present techniques.