The invention relates to a data processing method and device for an intelligent substation, and the method comprises the steps: receiving at least two types of data in SV data, opposite side data, analog quantity data and FT3 format data at the same time, employing an optical difference communication module to process the opposite side data, carrying out data interpolation of the opposite side data, and framing the interpolated data according to a set frame format; deframing the SV data by utilizing the calibration time of the opposite side data, storing the deframed SV data into a data cacheregion, performing data interpolation on the SV data, and framing according to a set frame format; converting the analog quantity data into a message through a conditioning circuit, storing the message into a data cache region, and framing according to a set frame format; and receiving the FT3 format data by adopting an optical fiber receiver, decoding the FT3 format data, and framing according toa set frame format. According to the invention, data of at least two formats can be processed at the same time, and the data can be analyzed, synchronized and framed, so that the problem that data ofmultiple formats cannot be processed at the same time in the prior art is solved.