A method and a device for displaying non-standard resolution data are provided. The method includes: reading signal source data and determining whether the signal source data is standard resolution data; in a case that the signal source data is non-standard resolution data, determining whether the non-standard resolution data is already stored in a memory; in a case that the non-standard resolution data is already stored in the memory, displaying the non-standard resolution data; and in a case that the non-standard resolution data is not stored in the memory, storing the non-standard resolution data in the memory and displaying the non-standard resolution data.