An image data retrieving method, comprising: receiving an image comprising a plurality of data images from a communication interface, wherein the data images comprise one or more characters or numbers; obtaining a plurality of regions of interest from the image, wherein each of the regions of interest is one of the plurality data images,; dividing the regions of interest into a plurality of groups based on a type of the plurality of data images, wherein at least one of the data images comprised in the regions of interest of each of the groups has a same type and the type of the plurality of data images comprises at least one of a string, an integer, a floating-point number, a font, a color, and a typeface size; combining the regions of interest of each of the groups into a to-be-recognized image; and creating a configuration file according to the regions of interest of each of the groups and the type of the at least one of the data corresponding to the regions of interest and so that another image received subsequently can be recognized according to the configuration file, performing an optical character recognition to the to-be-recognized image corresponding to each of the groups of different types respectively to obtain recognition results corresponding to the regions of interest of each of the groups, wherein the step of dividing the regions of interest into the groups comprises: establishing a first group of the groups according to a first region of interest of the regions of interest; converting the first region of interest into a binary image according to a configuration file; determining whether a sharpness of the binary image being greater than or equal to a sharpness threshold; performing the optical character recognition to the binary image when the sharpness of the binary image being greater than or equal to the sharpness threshold; converting the first region of interest into the binary image according to an adjusted configuration file when a recognition result of the optical character recognition to the binary image not matching a predetermined data corresponding to the first region of interest.; and converting the regions of interest into the binary image through a mask mode according to a configuration value, wherein the configuration value comprises a mask RGB value, a mask RGB boundary and a zoom ratio. receiving an image comprising a plurality of data images from a communication interface, wherein the data images comprise one or more characters or numbers; obtaining a plurality of regions of interest from the image, wherein each of the regions of interest is one of the plurality data images,; dividing the regions of interest into a plurality of groups based on a type of the plurality of data images, wherein at least one of the data images comprised in the regions of interest of each of the groups has a same type and the type of the plurality of data images comprises at least one of a string, an integer, a floating-point number, a font, a color, and a typeface size; combining the regions of interest of each of the groups into a to-be-recognized image; and creating a configuration file according to the regions of interest of each of the groups and the type of the at least one of the data corresponding to the regions of interest and so that another image received subsequently can be recognized according to the configuration file, performing an optical character recognition to the to-be-recognized image corresponding to each of the groups of different types respectively to obtain recognition results corresponding to the regions of interest of each of the groups, wherein the step of dividing the regions of interest into the groups comprises: establishing a first group of the groups according to a first region of interest of the regions of interest; converting the first region of interest into a binary image according to a configuration file; determining whether a sharpness of the binary image being greater than or equal to a sharpness threshold; performing the optical character recognition to the binary image when the sharpness of the binary image being greater than or equal to the sharpness threshold; establishing a first group of the groups according to a first region of interest of the regions of interest; converting the first region of interest into a binary image according to a configuration file; determining whether a sharpness of the binary image being greater than or equal to a sharpness threshold; performing the optical character recognition to the binary image when the sharpness of the binary image being greater than or equal to the sharpness threshold; converting the first region of interest into the binary image according to an adjusted configuration file when a recognition result of the optical character recognition to the binary image not matching a predetermined data corresponding to the first region of interest.; and converting the regions of interest into the binary image through a mask mode according to a configuration value, wherein the configuration value comprises a mask RGB value, a mask RGB boundary and a zoom ratio.