The invention discloses an information hiding method based on an H.265 video pixel domain. The information hiding method comprises the steps of embedding and extracting; in an embedding part, first performing preprocessing of secret information before an analysis of a high layer, namely an NALU unit, for video decoding; after a video is decoded to entropy decoding, embedding according to a pixel value of a time domain layer of a video source and an embedding rule, and after the embedding is finished, continuing to perform the video decoding at a CTU (Code Tree Unit) level; and in an extracting part, obtaining a carrier video which is embedded and is transmitted, and performing configuration of a video code; and before the code is compressed by an encoder, obtaining video time domain pixel data of a current CTU, performing extraction of the secret information according to an extraction rule, and after the secret information of the current CTU is extracted completely, continuing to perform encoding work of the CTU. According to the method provided by the invention, a video steganography is performed at a time domain level in video encoding and decoding, and an LSB bit of the time domain pixel value is directly modified, so the method has the advantages of easy implementation and good video sensory quality; and the increasing rate of embedded information to a code rate of the carrier video is very small.